|
San Francisco Bay Area 1990 Regional Travel Characteristics - WP #4 - MTC Travel Survey
Click HERE for graphic. Table of Contents Page 1.0 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . 1 2.0 Weekday 1990 Regional Travel. . . . . . . . . . . . . . . . . 5 2.1 Components of Regional Travel. . . . . . . . . . . . . 6 2.2 Weekday Travel by Trip Purpose and Travel Mode . . . . 9 2.3 Distribution of Weekday Trips by Time of Day . . . . .16 2.4 Reported Trip Duration by Trip Purpose and Travel Mode . . . . . . . . . . . . . . . . . . . . .30 3.0 Weekday 1990 Regional Household Trip Rates. . . . . . . . . .41 3.1 Regional Trip Rates by Trip Purpose and Travel Mode .41 3.2 Regional Trip Rates by Household Size . . . . . . . .43 3.3 Regional Trip Rates by Household Income . . . . . . .50 3.4 Regional Trip Rates by Vehicle Availability . . . . .56 3.5 Regional Trip Rates by Housing Structure Type. .61 3.6 Regional Trip Rates by County of Residence. . . . . .63 3.7 Regional Trip Rates by Workers in Household . . . . .66 3.8 Regional Trip Rates by Household Life Cycle . . . . .71 3.9 Regional Trip Rates by Household Size by Vehicle availability . . . . . . . . . . . . . . . . . . . .75 3.10 Regional Trip Rates by Household Size by Workers in Household . . . . . . . . . . . . . . . . .79 3.11 Regional Trip Rates by Workers in Household by Vehicle Availability . . . . . . . . . . . . . . . . . .83 3.12 Regional Trip Rates by Density-Based Area Type . . .87 4.0 Weekday 1990 Travel by Personal Characteristics . . . . . . .93 4.1 Travel by Age of Person. . . . . . . . . . . . . . . .93 4.2 Travel by Age and Gender of Person . . . . . . . . . 102 4.3 Travel by Employment Status and by Gender of Person. 108 4.4 Travel by Drivers License and by Gender of Person. . 112 4.5 Travel by Disability Status and by Gender of Person. 116 5.0 Weekday 1990 County Travel. . . . . . . . . . . . . . . . . 120 5.1 County Trips by Trip Purpose . . . . . . . . . . . . 120 5.2 County Trips by Travel Mode. . . . . . . . . . . . . 124 5.3 County-to-County Trips . . . . . . . . . . . . . . . 132 5.4 County-Level Vehicle Occupancy . . . . . . . . . . . 136 Appendices Appendix 1.0 . . . . . . . . . . . . . . . . . . . . . . . . . . 138 Appendix 2.0 . . . . . . . . . . . . . . . . . . . . . . . . . . 152 Appendix 3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . 179 Appendix 5.0 . . . . . . . . . . . . . . . . . . . . . . . . . . 195 References . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . . 209 LIST OF TABLES 1.1 Characteristics of Household Travel Surveys Conducted in the San Francisco Bay Area . . . . . . . . . . . . . . . . . . 4 2.1.1 Components of Regional Travel: Intraregional vs Interregional. . . . . . . . . . . . . . . . . . . . . . . 7 2.1.2 Intraregional and Interregional Trips by Trip Purpose. . . 8 2.2.1 1990 Regional Weekday Trips by Purpose and Detailed Travel Mode . . . . . . . . . . . . . . . . . . . . . . . . . . .12 2.2.2 1990 Regional Weekday Trips by Trip Purpose at Origin & Destination. . . . . . . . . . . . . . . . . . . . . . . .13 2.2.3 1990 Regional Weekday Trips by Trip Purpose and Travel Mode. . . . . . . . . . . . . . . . . . . . . .14 2.2.4 1990 Regional Weekday Vehicle Occupancy by Trip Purpose. .15 2.3.1 Distribution of 1990 Regional Weekday Trips by Time of Day - Time at Trip Origin: Comparison by Mode & Trip Purpose. .20 2.3.2 Distribution of 1990 Regional Weekday Trips by Time of Day - Time at Trip Destination: Comparison by Mode & Trip Purpose. . . . . . . . . . . . . . . . . . . . . . . . . .21 2.3.3 Distribution of Regional 1990 Weekday Trips-in-Motion by Time-of-Day: Percent Peak Hour of Daily & Percent Work Trips of Peak Hour . . . . . . . . . . . . . . . . . . . .22 2.4.1 Regional 1990 Weekday Reported Trip Duration by Purpose and Mode . . . . . . . . . . . . . . . . . . . . . . . . . . .33 2.4.2 Regional 1990 Trip Duration Frequency Distribution by Trip Purpose. . . . . . . . . . . . . . . . . . . . . . . . . .34 2.4.3 Regional 1990 Trip Duration Frequency Distribution by Travel Mode . . . . . . . . . . . . . . . . . . . . . . . . . . .38 3.1 1990 Regional Trip Rates by Purpose and Mode . . . . . . .42 3.2.1 1990 Regional Transit Share for Trips per Household by Household Size . . . . . . . . . . . . . . . . . . . . . .47 3.2.2 1990 Regional Household Characteristics by Household Size.49 3.3.1 1990 Regional Trips per Household by Household Income Tertile. . . . . . . . . . . . . . . . . . . . . . . . . .52 3.3.2 1990 Regional Trips per Person by Household Income Tertile . . . . . . . . . . . . . . . . . . . . . .53 3.3.3 1990 Regional Trips per Household by Household Income Quartile . . . . . . . . . . . . . . . . . . . . . . . . .54 3.3.4 1990 Regional Trips per Person by Household Income Quartile. . . . . . . . . . . . . . . . . . . . . .55 3.4.1 1990 Regional Transit Share for Trips per Household by Vehicle Availability . . . . . . . . . . . . . . . . . . .58 3.4.2 1990 Regional Household Characteristics by Vehicle Availability . . . . . . . . . . . . . . . . . . . . . . .60 3.5 1990 Regional Transit Share for Trips per Household by Structure Type . . . . . . . . . . . . . . . . . . . . . .62 3.6 1990 Regional Transit Share for Trips per Household by County of Residence. . . . . . . . . . . . . . . . . . . .65 3.7.1 1990 Regional Trips per Household by Workers in Household. . . . . . . . . . . . . . . . . . . . . . . . .68 3.7.2 1990 Regional Trips per Person by Workers in Household . .69 3.8.1 1990 Regional Trips per Household and per Person by Household Life Cycle . . . . . . . . . . . . . . . . . . .73 3.8.2 1990 Regional Trips per Household by Trip Purpose by Household Life Cycle . . . . . . . . . . . . . . . . . . .74 3.9.1 1990 Regional Trips per Household by Household Size by Vehicles Available per Household - Total Modes . . . . . .76 3.9.2 1990 Regional Trips per Person by Household Size by Vehicles Available per Household - Total Modes. . . . . . . . . . .77 3.9.3 1990 Households and Household Population by Household Size by Vehicles Available per Household. . . . . . . . . . . .78 3.10.1 1990 Regional Trips per Household by Household Size by Workers per Household - Total Modes. . . . . . . . . . . .80 3.10.2 1990 Regional Trips per Person by Household Size by Workers per Household - Total Modes. . . . . . . . . . . . . . . .81 3.10.3 1990 Households and Household Population by Household Size by Workers per Household . . . . . . . . . . . . . . . . .82 -ii- 3.11.1 1990 Regional Trips per Household by Workers per Household by Vehicles Available per Household - Total Modes. . . . .84 3.11.2 1990 Regional Trips per Person by Workers per Household by Vehicles Available per Household - Total Modes . . . . . .85 3.11.3 1990 Households and Household Population by Workers per Household by Vehicles Available per Household. . . . . . .86 3.12.1 1990 Regional Transit Share for Trips per Household by Area Type . . . . . . . . . . . . . . . . . . . . . . . . . . .90 3.12.2 1990 Regional Walk Share for Trips per Household by Area Type . . . . . . . . . . . . . . . . . . . . . . . . . . .91 3.12.3 1990 Regional Bicycle Share for Trips per Household by Area Type . . . . . . . . . . . . . . . . . . . . . . . . . . .92 4.1.1 Average Trips per Person and Trip Purpose Share by Age of Trip Maker . . . . . . . . . . . . . . . . . . . . . . . .95 4.1.2 Average Trips per Person and Trip Purpose Share by Age Group. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99 4.1.3 Modal Share for Work and Total Trips by Age Group. . . . 101 4.2.1 Share of Population Reporting Travel by Age and Gender . 105 4.2.2 Average Trips per Person and Trip Purpose Share by Age Group by Gender. . . . . . . . . . . . . . . . . . . . . . . . 106 4.2.3 Modal Share for Work and Total Trips by Age Group by Gender. . . . . . . . . . . . . . . . . . . . . . . . 107 4.3.1 Average Trips per Person and Trip Purpose Share by Employment Status by Gender. . . . . . . . . . . . . . . 110 4.3.2 Modal Share for Work and Total Trips by Employment Status by Gender . . . . . . . . . . . . . . . . . . . . 111 4.4.1 Average Trips per Person and Trip Purpose Share by Driver's License by Gender. . . . . . . . . . . . . . . . . . . . 113 4.4.2 Characteristics of Persons by Driver's License, Age and Gender . . . . . . . . . . . . . . . . . . . . . . . . . 114 4.4.3 Modal Share for Work and Total Trips by Driver's License by Gender . . . . . . . . . . . . . . . . . . . . . . . . . 115 4.5.1 Average Trips per Person and Trip Purpose Share by Disability Status by Gender. . . . . . . . . . . . . . . 118 4.5.2 Modal Share for Work and Total Trips by Disability Status by Gender. . . . . . . . . . . . . . . . . . . . . . . . 119 5.1.1 1990 Weekday Trips by Trip Purpose and County of Production . . . . . . . . . . . . . . . . . . . . . . . 122 5.1.2 1990 Weekday Trips by Trip Purpose and County of Attraction. . . . . . . . . . . . . . . . . . . . . . 123 5.2.1 1990 Weekday Home-Based Work Trips by Mode and County of Production . . . . . . . . . . . . . . . . . . . . . . . 127 5.2.2 1990 Weekday Home-Based Work Trips by Mode and County of Attraction . . . . . . . . . . . . . . . . . . . . . . . 128 5.2.3 Comparison of 1990 Census and 1990 Survey Modal Shares: Work Trips by County of Residence . . . . . . . . . . . . . . 129 5.2.4 1990 Weekday Total Trips by Mode and County of Production . . . . . . . . . . . . . . . . . . . . . . . 130 5.2.5 1990 Weekday Total Trips by Mode and County of Attraction . . . . . . . . . . . . . . . . . . . . . . . 131 5.3.1 1990 Home-Based Work Trip Productions, Attractions, and Intra-County Trips . . . . . . . . . . . . . . . . . . . 134 5.3.2 1990 Total Trip Productions, Attractions, and Intra-County Trips. . . . . . . . . . . . . . . . . . . . . . . . . . 135 5.4 1990 Vehicle Occupancy by Trip Purpose . . . . . . . . . 137 -iii- APPENDIX TABLES 2.2.2A 1990 Regional Weekday Trips by Detailed Purpose at Origin and Destination. . . . . . . . . . . . . . . . . . . . . 153 2.3.lA 1990 Dist. of Regional Weekday Trips by Time of Day: Total Modes: Time at Trip Origin . . . . . . . . . . . . . . . 154 2.3.2A 1990 Distribution of Regional Weekday Trips by Time of Day: Total Modes: Time at Trip Destination. . . . . . . . . . 155 2.3.3A 1990 Distribution of Regional Weekday Trips by Time of Day: Person Modes: Time at Trip Origin . . . . . . . . . . 156 2.3.4A 1990 Distribution of Regional Weekday Trips by Time of Day: Person Modes: Time at Trip Destination. . . . . . . . 157 2.3.5A 1990 Distribution of Regional Weekday Trips by Time of Day: Transit Modes: Time at Trip Origin . . . . . . . . . . 158 2.3.6A 1990 Distribution of Regional Weekday Trips by Time of Day: Transit Modes: Time at Trip Destination. . . . . . . . 159 2.3.7A 1990 Distribution of Regional Weekday Trips by Time of Day: Vehicle Driver Modes: Time at Trip Origin . . . . . . 160 2.3.8A 1990 Distribution of Regional Weekday Trips by Time of Day: Vehicle Driver Modes: Time at Trip Destination. . . . 161 2.3.9A 1990 Distribution of Regional Weekday Trips by Time of Day: Drive Alone Modes: Time at Trip Origin . . . . . . . . . 162 2.3.10A 1990 Distribution of Regional Weekday Trips by Time of Day: Drive Alone Modes: Time at Trip Destination. . 163 2.3.11A 1990 Distribution of Regional Weekday Trips by Time of Day:.Shared Ride Modes: Time at Trip Origin . . . . 164 2.3.12A 1990 Distribution of Regional Weekday Trips by Time of Day: Shared Ride Modes: Time at Trip Destination. . 165 2.3.13A Trips-in-Motion Analysis for 1990 Weekday Total Trips . . . . . . . . . . . . . . . . . . . . 166 2.3.14A Trips-in-Motion Analysis for 1990 Weekday Person Trips. . . . . . . . . . . . . . . . . . . . 167 2.3.15A Trips-in-Motion Analysis for 1990 Weekday Transit Trips . . . . . . . . . . . . . . . . . . . . . . . 168 2.3.16A Trips-in-Motion Analysis for 1990 Weekday Vehicle Driver Trips. . . . . . . . . . . . . . . . . . . . 169 2.3.17A Trips-in-Motion Analysis for 1990 Weekday Vehicle Passenger Trips . . . . . . . . . . . . . . . . . . 170 2.3.18A Trips-in-Motion Analysis for 1990 Weekday Walk Trips . . . . . . . . . . . . . . . . . . . . . . . 171 2.3.19A Trips-in-Motion Analysis for 1990 Weekday Bicycle Trips . . . . . . . . . . . . . . . . . . . . . . . 172 2.3.20A Trips-in-Motion Analysis for 1990 Weekday Home-Based Work Trips. . . . . . . . . . . . . . . . . . . . . 173 2.3.21A Trips-in-Motion Analysis for 1990 Weekday Home-Based Shop (Other) Trips. . . . . . . . . . . . . . . . . 174 2.3.22A Trips-in-Motion Analysis for 1990 Weekday Home-Based Social/Recreation Trips . . . . . . . . . . . . . . 175 2.3.23A Trips-in-Motion Analysis for 1990 Weekday Home-Based School Trips. . . . . . . . . . . . . . . . . . . . 176 2.3.24A Trips-in-Motion Analysis for 1990 Weekday Non-Home- Based Trips . . . . . . . . . . . . . . . . . . . . 177 2.3.25A Trips-in-Motion Analysis - Share of Trips by Trip Purpose by Time Period. . . . . . . . . . . . . . . 178 -iv- 3.2.1A 1990 Regional Trips per Household by Household Size. . . 180 3.2.2A 1990 Regional Trips per Person by Household Size . . . . 181 3.3.1A 1990 Regional Trips per Household by Detailed Household Income Group . . . . . . . . . . . . . . . . . . . . . . 182 3.3.2A 1990 Regional Trips per Person by Detailed Household Income Group. . . . . . . . . . . . . . . . . . . . . . . . . . 183 3.3.3A 1990 Regional Transit Share for Work and Total Trips per Household by Income. . . . . . . . . . . . . . . . . . . 184 3.4.1A 1990 Regional Trips per Household by Vehicle Availability . . . . . . . . . . . . . . . . . . . . . . 185 3.4.2A 1990 Regional Trips per Person by Vehicle Availability . 186 3.5.1A 1990 Regional Trips per Household by Housing Structure Type . . . . . . . . . . . . . . . . . . . . . 187 3.5.2A 1990 Regional Trips per Person by Housing Structure Type . . . . . . . . . . . . . . . . . . . . . 188 3.6.1A 1990 Regional Trips per Household by County of Residence. . . . . . . . . . . . . . . . . . . . . . . . 189 3.6.2A 1990 Regional Trips per Person by County of Residence. . 191 3.12.1A 1990 Regional Trips per Household by Density- Based Area Type. . . . . . . . . . . . . . . . . . . . . 193 3.12.2A 1990 Regional Trips per Household by Density-Based Area Type. . . . . . . . . . . . . . . . . . . . . . . . 194 5.3.1A 1990 County-to-County Home-Based Work Trips by Mode. . . 196 5.3.2A 1990 County-to-County Home-Based Shop (Other) Trips by Mode. . . . . . . . . . . . . . . . . . . . . . 198 5.3.3A 1990 County-to-County Home-Based Social/Recreation Trips by Mode . . . . . . . . . . . . . . . . . . . . . . . . . . 200 5.3.4A 1990 County-to-County Home-Based School Trips by Mode . 202 5.3.5A 1990 County-to-County Non-Home-Based Trips by Mode . . . 204 5.3.6A 1990 County-to-County TOTAL Trips by Mode. . . . . . . . 206 -v- LIST OF FIGURES 2.3.1 1990 Weekday Trips in Motion by Time-of-Day by Trip Purpose . . . . . . . . . . . . . . . . . . . . . . .23 2.3.2 1990 Weekday Home-Based Work Trips in Motion by Time- of-Day . . . . . . . . . . . . . . . . . . . . . . . . . .24 2.3.3 1990 Weekday Home-Based Shop (Other) Trips in Motion by Time-of-Day. . . . . . . . . . . . . . . . . . . . . . . .25 2.3.4 1990 Weekday Home-Based Social/Recreation Trips in Motion by Time-of-Day. . . . . . . . . . . . . . . . . . . . . . . .26 2.3.5 1990 Weekday Home-Based School Trips in Motion by Time-of- Day. . . . . . . . . . . . . . . . . . . . . . . . . . . .27 2.3.6 1990 Weekday Non-Home-Based Trips in Motion by Time- of-Day . . . . . . . . . . . . . . . . . . . . . . . . . .28 2.3.7 Trip Purpose Share by Time-of-Day. . . . . . . . . . . . .29 2.4.1 Trip Duration Frequency Distribution: Weekday Trips by Trip Purpose. . . . . . . . . . . . . . . . . . .37 3.2.1 1990 Trips per Household by Household Size and Trip Purpose . . . . . . . . . . . . . . . . . . . . . . .45 3.2.2 1990 Trips per Person in Household by Household Size and Trip Purpose . . . . . . . . . . . . . . . . . . . . . . .46 3.2.3 Regional Transit Share by Household Size . . . . . . . . .48 3.4.1 Regional Transit Share by Vehicle Availability.. . . . . .59 3.7.1 1990 Trips per Household by Workers in Household by Trip Purpose. . . . . . . . . . . . . . . . . . . . . . . . . .70 4.1.1 Average Total Trips per Person by Age of Trip Maker. . . .97 4.1.2 Share of Trips by Trip Purpose by Age of Trip Maker. . . .98 4.1.3 Share of Trips by Trip Purpose by Age Group. . . . . . . 100 -vi- 1.0 Introduction This working paper is the fourth in a series to document analysis and results from the 1990 MTC household travel survey. Previous working papers on the 1990 travel survey covered survey design issues, sample weighting and expansion, and trip linking procedures. Working paper #4 on the 1990 household travel survey is structured similarly to working paper #8 on the 1981 MTC household travel survey (1980 Regional Travel Characteristics: Working Paper #8: 1981 MTC Travel Survey, published June 1983.) The reader is encouraged to compare and contrast results from the 1981 and 1990 Bay Area travel surveys by using this working paper alongside the older report. The report structure and table numbering sequence are similar so as to assist in comparisons. The purpose of this paper is to report weighted and expanded results of the 1990 household travel survey in terms of regional and sub-regional travel characteristics. The focus of this research is 1990 average weekday, intraregional personal travel made by residents of the nine-county San Francisco Bay Area. Excluded from this analysis are weekend travel, interregional travel, commercial travel, and travel made by non-residents of the Bay Area. Weighted, expanded travel data in this report is based on the "single-weekday" sample from the 1990 household survey (see discussion below on the "single-weekday" versus "multiple-weekday" samples.) Section 2.0 of this report describes 1990 average weekday regional travel inferred from the 1990 household travel survey. This section includes information on the components of regional travel, travel by trip purpose and travel mode, travel by time-of- day, and reported trip duration. Section 3.0 of this working paper describes average regional household trip rates (trips per household, trips per person-in- household) by various classifications. Trip rates are reported by trip purpose and by travel mode. Section 4.0 of this working paper discusses travel patterns classified by the personal characteristics of the trip maker. These characteristics include age, gender, employment status, drivers license status, and disability status. (Note that there is not a comparable section in the 1981 travel survey working paper #8 on travel patterns by personal characteristics.) -1- Section 5.0 of this working paper reports on county-level trip rates and county-to-county travel patterns inferred from the weighted, expanded survey data files. Appendices to Working Paper #4 provide additional detailed information to augment the main set of tables. The appendix tables contain detailed information on travel by time-of-day (time at trip start, time at trip destination, "trips-in-motion"), detailed trip rates by trip purpose by travel mode by various categories, and detailed county-to-county person trip tables by trip purpose and travel mode. Appendix #1 to Working Paper #4 includes copies of the telephone interview forms used in the 1990 survey; and copies of the trip diary cards and instructions mailed to survey respondents. Background: Household Travel Surveys in the San Francisco Bay Area The 1990 MTC household travel survey is the third household travel survey conducted in the Bay Area over the past 25 years. Characteristics of these three surveys are summarized in Table 1.1. The first major survey, the 1965 home-interview survey, collected weekday and weekend daily travel data from over 30,000 Bay Area households. This was a traditional face-to-face "home interview" survey, where staff of the Bay Area Transportation Study Commission (BATSC) went into the homes of Bay Area residents to conduct the survey. In addition to the traditional household travel survey, the 1965 survey efforts included truck/taxi surveys and other auxiliary surveys for development of a comprehensive regional transportation planning database. The second major household travel survey in the Bay Area was conducted in 1981. This was a telephone survey, where initial contacts were made by telephone; travel diary cards were mailed to participating households; and travel diary data was retrieved in follow-up phone calls. The 1981 survey collected weekday and weekend daily travel data from over 7,000 households during the spring of 1981. The 1990 household travel survey was similar to the 1981 survey in terms of respondent contact and data collection techniques. The 1990 survey collected single weekday travel data from nearly 9,400 Bay Area households and multiple-weekday travel data from nearly 1,500 Bay Area households. The 1990 survey effort also included a separate sub-project, funded by the Bay Area Rapid Transit District, to -2- collect multiple-weekday travel data from 1,000 BART-using households. (The BART-using households were identified and contacted based on responses to on board surveys conducted by the BART District in 1988 and 1989). The BART survey and the MTC multiple-weekday survey were completed in the spring of 1990; the MTC single-weekday survey was continued and completed during the autumn of 1990. The MTC/BART multiple-weekday household travel surveys were the first large scale attempt at collecting multiple-weekday travel data in the United States. This database will be used for exploratory analysis into the day-to-day variability of travel within the Bay Area as well as other research and travel model development exercises. Other international multiple-weekday household travel surveys include the 1973 Reading, England surveys; the 1971 Uppsala, Sweden surveys; and the 1984 wave of the Dutch National Mobility Panel Survey. Recent (1994) efforts at conducting multiple-weekday surveys include the Portland, Oregon Metropolitan Service District (Metro) household travel surveys. Working Paper #4 results are based on the MTC single-weekday household travel survey sample, not the multiple-weekday sample. -3- Table 1.1 Characteristics of Household Travel Surveys Conducted in the San Francisco Bay Area Click HERE for graphic. -4- 2.0 Weekday 1990 Regional Travel This section reports the aggregate total number of weekday trips made by Bay Area residents in 1990. The trips are estimated from the weekday daily travel diaries from the MTC "single-day" sample. Appendix 1 provides information on the detailed survey data items, definitions and abbreviations used in this working paper. The detailed trip purposes recorded in this survey are aggregated to five general purposes: - Home-Based Work - Home-Based Shop (Other) - Home-Based Social/Recreation - Home-Based School - Non-Home-Based A distinction is made between "home-based" and "non-home- based" trips. Homebased trips are those that start or end at the residence of the tripmaker. Non-homebased trips are those that have neither trip end at home. Home-based work trips are those made by employed persons directly from home-to-work and work-related business, and back to home. Home-based social/recreation trips are those made by household members from home-to-visit, eat a meal, recreation, and back to home. Home-based school trips are those made by students from home-to-school and school-to-home. Home-based shopping is a catchall category for the balance of home-based trips. It includes grocery shopping, comparison and convenience shopping, personal business, medical/dental, serving or "escorting" passengers, other trip purposes, and back-to-home. In a similar manner to trip purposes, the 24 survey travel modes are aggregated to seven general means of transportation: - Vehicle Driver - Vehicle Passenger - Transit Passenger - School Bus Passenger - Walk - Bicycle - Other Vehicle driver includes automobile driver, truck driver, van driver, and motorcycle driver. Vehicle passenger includes auto, truck, van and motorcycle passengers. Transit includes all public bus, rail and ferry passenger modes. Walk, school-bus and bicycle are stand alone travel modes. Mode other is a catchall category to include airplane, moped, and "other" (e.g., skateboard, rollerblades, wheelchair, horse, boat). -5- 2.1 Components of Regional Travel The purpose of this subsection is to identify the different travel markets that comprise regional travel in the Bay Area, and to understand the nature and scope of the 1990 household travel survey in providing information on these markets. Regional travel can be characterized in several dimensions. The first dimension discussed is that of commercial versus personal travel. Commercial trips are made by drivers (and possibly passengers) of commercial vehicles as part of their daily work activities. Commercial trips include the delivery of goods, services, and passengers (bus drivers, train operators). Personal trips are made to satisfy the travel demands of households and household members. A second dimension of regional travel is by internal trips versus external trips. These are also known as the intraregional versus interregional travel markets. Intraregional trips are those trips both beginning and ending in the same region. Interregional trips have at least one trip end located outside the region. Interregional trips may also be through trips, with neither end of a trip located in the region. A third dimension of regional travel is for resident and non- resident travel. Resident travel within a region is self-evident. Non-resident travel can be further broken down into tourist travel, work business travel, personal business travel and commute travel. Non-resident travel can be either intraregional (both ends of the trip within the Bay Area) or interregional (typically, commuters from the Central Valley commuting to jobs in the Bay Area). Since the 1990 Bay Area household travel survey was based on Bay Area resident households, no information on nonresident travel patterns are available, or reported from this survey. Bay Area resident intraregional and interregional trips are summarized in Table 2.1.1. Both sample and expanded trips are shown. Of the 17.1 million daily person trips in the Bay Area, 1.2 percent are interregional and 98.8 percent are intraregional. Intraregional and interregional trips by the five general trip purposes are shown in Table 2.1.2. Interregional trips tend to be oriented to home-based social/recreation travel as well as non- home-based travel (neither end of the trip at the residents' home). Overall, 26.3 percent of Bay Area residential trips are home-based work trips; 24.9 percent are home-based shop (other); 11.1 percent are home-based social/ recreation; 9.7 percent are home-based school; and 28.0 percent are non-home-based. -6- Table 2.1.1 Components of Regional Travel: Intraregional vs Interregional Click HERE for graphic. -7- Table 2.1.2 Intraregional and Interregional Trips by Trip Purpose Click HERE for graphic. -8- 2.2 Weekday Travel by Trip Purpose and Travel Mode This section reports on the expanded, weekday travel by trip purpose and travel mode. This consists of the region's 17 million intraregional daily person trips. Regional trips by the detailed travel modes and the five general trip purposes are shown in Table 2.2.1. The lower part of Table 2.2.1 shows regional trips with travel modes aggregated to seven general travel means by five general trip purposes. Twenty- four separate modes were collected in the 1990 survey. The largest share and number of trips in the Bay Area is automobile drivers, at 10.7 million out of the 17.0 million regional trips, or 63 percent of all trips. The second largest market is automobile passengers, comprising 2.7 million trips, 16.2 percent of all trips. Walk trips are the third largest travel mode, with 1.7 million daily walk trips, or 9.9 percent of all daily trips in the region. After walk trips, public bus passengers account for 691,000 trips (4.1 percent); bicycle trips are 254,000 trips (1.5 percent); and BART (Bay Area Rapid Transit) accounts for 252,000 daily trips (1-5 percent). Transit trips comprise 6.3 percent of all trips in the Bay Area in 1990. Bus passengers are 64.3 percent of all transit riders in the Bay Area, followed by BART with 23.4 percent of transit ridership; and streetcar modes with 4.6 of all transit ridership. Table 2.2.1 can also be used to characterize the trip purpose share for transit submodes. Overall, 41.8 percent of all transit trips are home-based work. In comparison, 61.5 percent of BART trips and 80 percent of CalTrain trips are home-based work. Regional trips by general purpose at trip origin and general purpose at trip destination are summarized in Table 2.2.2. (Regional trips by detailed trip origin purpose and detailed trip destination purpose are summarized in appendix Table 2.2.2A.) The trip purposes "work" and "work-related" are broken out separately in this table. This information is useful in showing some of the imbalances in homebased work trips depending if the home-end of a trip is the origin or destination. Note that regional home-to-work trips (2.24 million) are 18.6 percent higher than work-to-home trips (1.89 million). This is because people are more likely to divert from their work-to-home commute to take care of personal business or shopping trips. In the morning (typical home-to-work and home-to-school commute) workers (and students) are more likely to head directly to work (or school). -9- Note that the largest non-home-based (NHB) submarket is for shop (other)- to shop(other) trip purposes (1.01 million out of 4.72 million trips). The second largest non-home-based submarket are the work-to-social/recreation and social/recreation to-work trips (723,000) which are, for the most part, midday work-to-lunch and lunch-to-work trips. Non-home-based trips can further be broken down into non-home-based work-or-work-related trips (NHBW) at 2.55 million trip s (54 percent of all NHB trips); and non- home-based non-work trips (NHBNW) at 2.17 million trips (46 percent of all NHB trips). Regional trips by general trip purpose and general travel mode are shown in Table 2.2.3. The row percentages in this table are mode-specific trip purpose shares. The column percentages are purpose-specific modal shares. Vehicle driver mode shares range from 21 percent for home-based school trips to 78 percent for home- based work trips. Vehicle passenger mode shares range from a low of 12.2 percent for home-based work trips to a high of 26.3 percent for home-based shop (other) trips. Transit mode shares for home-based shop, home-based social/recreation and non-home-based trip purposes are approximately the same at 3.3 to 4.3 percent of all trips. Home- based work trips (10.0 percent) and home-based school trips (11.3 percent) have significantly higher transit shares. Bicycle mode shares range from 0.9 percent of non-home-based trips to 4.2 percent of home-based school trips. The home-based work bicycle share is 1.3 percent. Walk mode shares range from 3.0 percent of home-based work trips to 21.5 percent of home-based school trips. The plurality of regional transit trips (41.8 percent) are for home-based work trips. In contrast, only 8.1 percent of regional walk trips are from home-to-work or work-to-home. The plurality of regional walk trips (38.4 percent) are non-home-based trips. Note that the mode "school bus passenger" are assigned exclusively to the homebased school trip purpose. Trips where the respondent reported travel as a school bus passenger, but for other than school trip purposes, are grouped together in most of the analyses in this working paper as mode "other." Regional vehicle occupancy rates are reported in Table 2.2.4. Vehicle occupancy is obtained by dividing the sum of vehicle driver and vehicle passenger trips by the number of vehicle driver trips. The regional vehicle occupancy in the Bay Area in 1990 is 1.258 persons per vehicle. This ranges from a low of 1.099 persons per vehicle -10- for home-based work trips to a high of 2.521 persons per vehicle for home-based school trips. These vehicle occupancy calculations are basically rough estimates, given that any particular vehicle trip may contain multiple passengers (driver, passengers) with different trip purposes. The driver may be escorting his or her child from home- to school. This is a "home-based shop (other)" trip for the vehicle driver (the parent) yet is classified as a "home-based school" trip for the child. Another example is a parent escorting a child to school and then continuing on to work. In the MTC linked-trip procedures, the parent's trip will be considered a home-to-work trip with a vehicle occupancy of two persons. Table 2.2.1 1990 Regional Weekday Trips by Purpose and Detailed Travel Mode Click HERE for graphic. -12- Table 2.2.2 1990 Regional Weekday Trips by Trip Purpose at Origin & Destination Click HERE for graphic. Notes: Upper entry is number of trips. Middle entry is row percent. Lower entry is column percent. -13- Table 2.2.3 1990 Regional Weekday Trips by Trip Purpose and Travel Mode Click HERE for graphic. Notes: Upper entry is number of trips. Middle entry is row percent. Lower entry is column percent. -14- Table 2.2.4 1990 Regional Weekday Vehicle Occupancy by Trip Purpose Click HERE for graphic. -15- 2.3 Distribution of Weekday Trips by Time of Day This section reports on the regional expanded, weekday travel by time of day. Appendix 2.3 contains 25 tables with detailed data related to travel by time of day. Time of day travel is analyzed using three methods: 1) analysis of trips by reported time of departure (time at trip origin); 2) analysis of trips by reported time of arrival (time at trip destination); and 3) analysis of trips by what is called "trips in motion." The first two methods are self-explanatory. The "trips in motion" computer program assigns each trip to a time period or time periods based on time at trip origin and time at trip destination. For example, if a person reported a home-to-work trip departing home at 7:55 AM and arriving at work at 8:25 AM, then that trip would be allocated to three AM peak hour time periods (based on a 15 minute analysis): the 7:45-to-8:45 AM peak hour; the 8:00-to-9:00 AM peak hour; and the 8:15-to-9:15 AM peak hour. The number of "trips in motion" reflects the number of total trips (specified by trip purpose, travel mode, etc.) that occur, or are "in motion" anytime during the specified time period. Distribution of trips by time of day based on time at trip origin are summarized in Table 2.3.1. Trips by time of day based on time at trip destination are shown in Table 2.3.2. These two tables summarize travel by AM and PM peak hour and peak periods. Percentages show the AM and PM peak hour trips, stratified by trip purpose and travel mode, as a share of daily totals. Detailed appendix tables based on time at trip origin and trip destination are included as Tables 2.3.lA through 2.3.12A. These summaries show that 8.3 percent of all regional daily trips start in the AM peak hour (7:00-8:00 AM) and 9.2 percent of all regional trips start in the PM peak hour (4:30-5:30 PM) (Table 2.3.1). Trips made by transit passengers are more peak hour oriented than total trips, with 14.8 percent of all daily transit passenger trips start in the AM peak hour (7:00-8:00 AM) and 11.9 percent start in the PM peak hour (4:30-5:30 PM). Trips made by vehicle drivers (the mode "vehicles" in Tables 2.3.1 and 2.3.2) are more spread out than for transit passengers, with 7.6 percent starting in the AM peak hour and 9.7 percent in the PM peak hour. (The mode "commuters" in Tables 2.3.1 and 2.3.2 includes vehicle drivers, vehicle passengers, and transit passengers.) These tables are also useful in showing the peaking patterns based on trip purpose (home-based work, home-based school, total home-based, non-home-based), and by -16- time period (AM and PM peak hour, peak two-hour period, and peak three-hour period). The reader can use these tables (and the appendix tables) to understand the trip purpose share for peak hour or peak periods to evaluate the concentration of work trips versus non-work trips by time of day. Data from the Table 2.3.1 and the related appendix tables can be used by transportation planners to develop sets of peaking factors to apply to daily trip tables by trip purpose and travel mode for use in travel demand model forecasting systems. MTC typically uses the data from time-at-trip-origin for estimating these peaking factors, though the analyst may choose to experiment with averages based on time-at-trip-origin and time-at-trip- destination factors. AM peak hour and PM peak hour factors based on regional trips- in-motion analysis are shown in Table 2.3.3. Appendix tables 2.3.13A through 2.3.25A provide detailed information on regional trips-in-motion by trip purpose and travel mode. The trips-in- motion summary table confirms the information in the time-at-trip- origin analysis, namely, that transit trips are more peak hour oriented (peaked) than vehicle driver trips. Again, the mode "commuter-person" is a sum of vehicle driver, vehicle passenger, and transit passenger trips. The trips-in-motion analysis shows that 63.6 percent of ali vehicle trips-in-motion during the AM peak hour (7:30-8:30 AM) are made by commuters going from home-to-work. This table also shows that just 43.8 percent of all vehicle trips-in-motion during the PM peak hour (4:45-5:45 PM) are made by commuters going from work-to- home. This indicates that the PM peak hour has a significantly larger share of non-work trips occurring than during the AM peak hour. This holds true except for transit trips-in-motion, where the majority of transit trips occurring in both the AM and PM peak hours are either from home-to-work or work-to-home. (The reader should note that trips-in-motion analyses are only provided for hour long periods. Multi-hour peak period trips-in- motion could be developed, but the reader is encourage to use the time-at-trip-origin and time-at-trip-destination data for multi- hour peak period analyses.) The trips-in-motion analyses by trip purposes are charted in Figures 2.3.1 through 2.3.7. Figure 2.3.1 shows the composite time-of-day analysis with the five general trip purposes stacked one on top of each other. This useful graphic presents information related to the bi-modal distribution of home-based work trips as well as the predominance of non-work trips during midday and PM peak periods. (This graphic -17- is based on data contained in appendix Table 2.3.25A). Figures 2.3.2 through 2.3.6 graph the time-of-day distribution of trips separately by trip purpose. The reader can note that the bi-modal distributions of home-based work trips and home-based school trips are similar to the two humps of a bactrian camel (see below). The uni-modal distributions of home-based shop (other), homebased social/recreation, and non-home-based trips are similar (in a fashion) to the one hump of the dromedary camel. Click HERE for graphic. For work trips (Figure 2.3-2), the AM peak hour "hump" occurs between 7:30 and 8:30 AM; the PM peak hour "hump," between 4:45 and 5:45 PM (Figure 2.3.2). For home-based school trips (Figure 2.3-5), the AM peak hour "hump" is also the 7:30 to 8:30 hour, whereas the PM peak hour for school trips occurs between 2:30 and 3:30 PM, over two hours earlier than the PM peak commute work-trip rush hour. Home-based shop (other) trips (Figure 2.3.3) show a complicated peaking pattern, with minor AM peak hour "humps" at 7:45 to 8:45 AM; a less pronounced midday "hump" at 11:30 AM to 12:30 PM; and the largest "hump" at 2:45 to 3:45 in the afternoon. This is basically a "uni-modal" distribution with minor humps during the AM peak hour and the midday (e.g., lunch hour shopping trips). Home-based social/recreation trips (Figure 2.3.4) show a very pronounced and peaked uni-modal distribution, peaking at 6:30 to 7:30 PM in the evening. These are primarily trips from dinner (eat meal)-to-home or from visiting friends-to-home. -18- Non-home-based trips (Figure 2.3.5) also show a very pronounced and peaked uni-modal distribution by time-of-day, peaking during the 11:45 AM to 12:45 PM noon hour. These midday non-home-based trips are primarily the 'lunch bunch" type of trips, with persons going from work (or school) to lunch and back to work (or school) again at the end of their regular lunch period. There is also a minor "hump" of non-home-based trips occurring at 4:30 to 5:30 in the afternoon. This afternoon surge of non-home-based trips are the typical trips made by a commuter on the way home from work, stopping off to do grocery shopping, picking up clothes at the dry cleaners, picking up a six-pack at the liquor store, etc. The cumulative frequency distribution of travel by trip purpose by time-of-day is graphed in Figure 2.3-7. This graphic can be deceiving since the size of the travel market (e.g., 3:00-4:00 AM) isn't taken into account in this depiction of travel. It is, however, visually quite interesting, and may help the reader in understanding who is traveling for what purpose" for any particular hour of the day. -19- Table 2.3.1 Distribution of 1990 Regional Weekday Trips by Time of Day - Time at Trip Origin Comparison by Mode & Trip Purpose Click HERE for graphic. Table 2.3.2 Distribution of 1990 Regional Weekday Trips by Time of Day - Time at Trip Destination Comparison by Mode & Trip Purpose Click HERE for graphic. Table 2.3.3 Distribution of Regional 1990 Weekday Trips-in-Motion by Time-of- Day Percent Peak Hour of Daily & Percent Work Trips of Peak Hour Click HERE for graphic. -22- Figure 2.3.1 1990 Weekday Trips in Motion by Time-of-Day by Trip Purpose Click HERE for graphic. -23- Figure 2.3.2 1990 Weekday Home-Based Work Trips in Motion by Time-of-Day Click HERE for graphic. -24- Figure 2.3.3 1990 Weekday Home-Based Shop (Other) Trips in Motion by Time-of-Day Click HERE for graphic. -25- Figure 2.3.4 1990 Weekday Home-Based Social/Recreation Trips in Motion by Time- of-Day Click HERE for graphic. -26- Figure 2.3.5 1990 Weekday Home-Based School Trips in Motion by Time-of-Day Click HERE for graphic. -27- Figure 2.3.6 1990 Weekday Non-Home-Based Trips in Motion by Time-of-Day Click HERE for graphic. -28- Figure 2.3.7 Trip Purpose Share by Time-of-Day Click HERE for graphic. -29- 2.4 Reported Trip Duration by Trip Purpose and Travel Mode This section of Working Paper #4 discusses the average trip duration as reported by survey respondents as well as frequency distributions of trip duration and reported trip start times. The 1990 household travel survey asked respondents to record the beginning and ending time for each of their trips for the entire day. Trip duration is then calculated as the difference between the beginning and ending times. Survey respondents have a strong tendency to round off and report trip times to the nearest five minutes. Respondents also have a strong tendency to report trip start times beginning on the hour, half-hour, or on the quarter-hour. This tendency to round off when reporting travel times and trip duration results in "spiky" frequency distribution of responses, with spikes at intervals of five minutes (in the case of reported trip duration) or with spikes at quarter-hour intervals (in the case of reported trip start time). The following table shows the distribution of regional weekday trips by recorded starting minute, comparing the 1990 Bay Area household travel survey to the 1990 Nationwide Personal Transportation Survey (NPTS): Click HERE for graphic. The Bay Area household travel survey analysis indicates that nearly half of Bay Area trips are reported to start either on-the- hour or on-the-half-hour. Respondents to the NPTS survey show a higher tendency (64.0%) to report trips starting on-the hour or on- the-half-hour. In the Bay Area, 35.0 percent of trips are reported to start -30- at times other than the quarter-hour; for the NPTS, 18.1 percent of all trips start at "all other" times. In a similar manner, survey respondents tend to round off and report the duration of their trips to the nearest five minutes. The following table highlights these findings: Click HERE for graphic. This table shows that 82 percent of all trips in the 1990 survey are reported to the nearest five minutes for all trips 60 minutes or less. Only 17.6 of all trips are reported at either travel times larger than 60 minutes (i.e., 4.1 percent of all trips) or at all other travel times (i.e., 13.5 percent of all trips). The most common answer to the average travel time questions for the 1990 survey is 10 minutes (16.6 percent of all trips), followed closely by trips reported at 15 minutes duration (16.4 percent of all trips). Regional average reported trip duration, by trip purpose and travel mode, is shown in Table 2.4.1. The average (mean) trip in the Bay Area in 1990 is 21.4 minutes in duration. This ranges from a low of 17.1 minutes per trip for home-based shop trips -31- to a high of 29.3 minutes for home-based work trips. (The 1990 survey-reported work trip duration of 29.3 minutes is nearly 11 percent higher than the 1990 Census reported commute duration of 26.5 minutes.) By means of transportation, walk trips are the shortest in duration, at an average of 14.0 minutes per one-way walk trip. This compares to public transportation where the average door-to- door reported trip duration in 47.2 minutes. Note that the public transportation travel time includes access and egress time (walking, driving to station) and waiting time. Also note that the mode "person commuter" includes vehicle driver, vehicle passenger and transit passenger. The frequency distribution of trips by reported trip duration by trip purpose is shown in Table 2.4.2. The three sub-tables in Table 2.4.2 show the number of trips, the percent of the column totals by trip purpose, and the cumulative percent of column totals by trip purpose. This data is also graphed in Figure 2.4.1. This chart is useful in showing the spikiness of the distribution at intervals of 15, 30, 45 and 60 minutes, even with the level of aggregation at five minute intervals. The median travel time for all non-work trips is 15 minutes. The median travel time for home- based work trips is 24.6 minutes. The frequency distribution of trips by reported trip duration by travel mode is shown in Table 2.4-3. The three sub-tables for Table 2.4.3 show the number of trips, the percent of trips, and the cumulative percent. The cumulative frequency distribution for regional walk trips shows that 76.6 percent of all walk trips are 15 minutes or less in duration. This contrasts to transit passenger trips where only 10.2 percent of transit passenger trips are 15 minutes or less. The median walk trip duration is about 9.6 minutes; for transit passenger trips, the median trip duration is 45 minutes. -32- Table 2.4.1 Regional 1990 Weekday Reported Trip Duration (in Minutes) by Purpose and Mode Click HERE for graphic. + Value is based on less than 50 sample trips and is shown for information purposes only. -33- Table 2.4.2 Regional 1990 Trip Duration Frequency Distribution by Trip Purpose Click HERE for graphic. -34 - Table 2.4.2 (continued) Regional 1990 Trip Duration Frequency Distribution by Trip Purpose Click HERE for graphic. -35- Table 2.4.2 (continued) Regional 1990 Trip Duration Frequency Distribution by Trip Purpose Click HERE for graphic. -36- Figure 2.4.1 Trip Duration Frequency Distribution Weekday Trips by Trip Purpose Click HERE for graphic. -37- Table 2.4.3 Regional 1990 Trip Duration Frequency Distribution by Travel Mode Click HERE for graphic. -38- Table 2.4.3 (continued) Regional 1990 Trip Duration Frequency Distribution by Travel Mode Click HERE for graphic. -39- Table 2.4.3 (continued) Regional 1990 Trip Duration Frequency Distribution by Travel Mode Click HERE for graphic. -40- 3.0 Weekday 1990 Regional Household Trip Rates This section summarizes aggregate trip rates by market segment, reporting the number of average (mean) trips per household and per person in household. The market segments used in this analysis are those typically used by transportation planners in analyzing travel behavior, namely: household size, household income, vehicle ownership level, housing structure type, geographic area of residence, workers in the household, household life cycle stage and land use density. The trips, households and persons that this analysis is based on are from the intraregional expanded, weighted 1990 Bay Area household travel survey "single day" sample. 3.1 Regional Trip Rates by Trip Purpose and Travel Mode Regional trip rates by trip purpose and travel mode for trips per household, trips per person age five years and over, and trips per total persons in household, are shown in Table 3.1. These trip rates are based on a weighted, expanded count of 2,246,251 regional households; 5,329,955 persons-in-households age five years and over; and 5,873,094 total persons-in-households. The average regional household in the Bay Area made just over 7.5 trips per weekday in 1990. By trip purpose, the average household made 1.99 home-based work trips per day; 1.89 home-based shop (other) trips per day; 0.83 home-based social /recreation trips per day; 0.74 home-based school trips per day; and 2.10 non-home-based trips per day. By travel mode, the average regional household made about 4.86 vehicle trips per average weekday, and just under one-half (0.48) transit trips per average weekday. The mode "in-vehicle person" is the combination of vehicle driver and vehicle passengers (excluding transit passengers). The mode "person" is the combination of vehicle driver, vehicle passenger and transit passenger modes. The average person residing in households in the Bay Area, age five and over, made 3.18 daily trips per person in 1990. Also reported is the same number of trips divided by the entire household population, including infants and toddlers ages 0 to 4, at 2.89 trips per person. -41- Table 3.1 1990 Regional Trip Rates by Purpose and Mode Click HERE for graphic. Note: Trip rates based on expanded survey households (2,246,251); population age 5+ (5,329,955); and total household population (5,873,094). -42- 3.2 Regional Trip Rates by Household Size This section summarizes aggregate trip rates by household size, reporting the average numbers of trips per household. Trip rates are reported for households of one, two, three, four, and five-or-more persons in the household. Appendix Tables 3.2.IA (trips per household) and 3.2.2A (trips per person) provide detailed trip rates by trip purpose and travel mode. The regional distribution of households and household population by the five household size categories is shown below: Click HERE for graphic. Trips per household by trip purpose by household size are graphed in Figure 3.2-1. Trips per household range from 3.6 trips for the average one-person household to a high of 14.3 trips for the average five-plus-person household. Home-based school trips per household are noticeably higher in the larger household size groups due to the presence of school-age children in households. Trips per person by trip purpose by household size are depicted in Figure 3.2-2. One person households have the highest number of trips per person at 3.6 trips per weekday. This contrasts to the five-plus household size group with 2.4 trips per person per weekday. The higher trips per person trip rate for lower household size groups is due to the need for small households to conduct all of the household's activities: work trips, shopping errands, personal business errands, etc. Larger households can spread the chores and errands more efficiently among the different household members, essentially lowering the overall trips per person trip rates. Note that home-based work and non-home-based trips per person decreases with increasing household size; home- based school trips per person increases with increasing household size due to the presence of children in the household. Home-based shop and home-based social/recreation trips show a tendency to have fewer -43- trips per person with increasing household size. Transit and total trips per household for home-based work and total purposes are shown, by household size, in Table 3.2.1. Transit shares are also graphed in Figure 3.2-3. Transit shares are highest for one-person households and lowest for four person households. Transit shares for five-or-more person households are slightly higher than those for four-person households. For home- based work trips, the average regional one-person household takes transit 17.3 percent of the time; the average regional four-person household takes transit for 7.0 percent of all work trips. Similarly, transit shares for total trips range from a high of 10.1 percent for one-person households to a low of 4.7 percent for four- person households. Other demographic characteristics of Bay Area regional households, stratified by the five household size groups, are presented in Table 3.2.2. Data is shown for income per household, income per person, vehicles per household, vehicles per person, average age of the household head, and average age of all persons in household (age five-or-more). This is useful in showing the inverse relationship between household size and income per capita, vehicles per capita, and age of the householder and members of the households. One person households tend to have the highest per capita incomes, the highest vehicles per capita, and tend to be older residents. Large households have school-age children who are not as likely to be employed and contributing to the household's income and who are not as likely to own or operate a motor vehicle. Children also have a tendency to bring down the average age in a household. -44- Figure 3.2.1 1990 Trips per Household by Household Size and Trip Purpose Click HERE for graphic. -45- Figure 3.2.2 1990 Trips per Person in Household by Household Size and Trip Purpose Click HERE for graphic. -46- Table 3.2.1 1990 Regional Transit Share for Trips per Household by Household Size Click HERE for graphic. -47- Figure 3.2.3 Regional Transit Share by Household Size Click HERE for graphic. -48- Table 3.2.2 1990 Regional Household Characteristics by Household Size Click HERE for graphic. -49- 3.3 Regional Trip Rates by Household Income This section summarizes aggregate trip rates by household income group, reporting the average numbers of trips per household. Trip rates are reported for households by household income tertile (three groups: < $30,000; $30,000-$60,000, $60,000+) and by household income quartile (four groups: < $25,000; $25,000-$45,000; $45,000$75,000; and $75,000+). This analysis of trip rates by household income is conducted on reported household income, not imputed household income. Household income groups were imputed (e.g., assigned based on the characteristics of the sample households with and without valid income codes) for the approximately 31 percent of survey respondents who refused, or did not know, their total household income. Appendix Tables 3.3.1A (trips per household) and 3.3.2A (trips per person) provide detailed trip rates by trip purpose and selected modes for the fifteen detailed household income groups collected in the 1990 survey. The regional distribution of households and household population by the household income tertiles is shown below: Click HERE for graphic. Trips per household by trip purpose and travel mode by household income tertile is shown in Table 3.3.1. Low income households made an average of 5.8 trips per weekday in 1990; high income households, 10.3 trips per household. Transit shares for trips by trip purpose are also shown in Table 3.3.1. For home-based work trips, transit shares range from a high of 16.2 percent for low income households to a low of 8.6 percent for high income households. For total trip purposes, transit shares range from a high of 10.9 percent for low income households, to 4.1 percent for high income households. Households who refused to provide or did not know their -50- household income are somewhere between "low income" and "medium income" in terms of total trips per household (6-5 trips) and transit share (7.1 percent for total trip purposes). Trips per person by trip purpose and travel mode by household income tertile is shown in Table 3.3.2. Trips per person increases with household income level, rising from 2.7 trips per person for low income households, to 3.1 trips per person for medium income households, to a high of 3.4 trips per person for high income households. The regional distribution of households and household population by the household income quartiles is shown below: Click HERE for graphic. Trips per household and per person, by trip purpose and travel mode by household income quartile is shown in Table 3.3.3 and 3.3.4, respectively. Total trips per household range from 5.5 trips for low income households (< $25,000) to 10.5 trips per average weekday for high income households (> $75,000). All purpose transit shares range from 12.5 percent for low income households to 3.7 percent for high income households. As with the income tertile analysis, trips per person increases with increasing household size. -51- Table 3.3.1 1990 Regional Trips per Household by Household Income Tertile Click HERE for graphic. -52- Table 3.32 1990 Regional Trips per Person by Household Income Tertile Click HERE for graphic. -53- Table 3.3.3 1990 Regional Trips per Household by Household Income Quartile Click HERE for graphic. -54- Table 3.3.4 1990 Regional Trips per Person by Household Income Quartile Click HERE for graphic. -55- 3.4 Regional Trip Rates by Vehicle Availability This section describes household trip rates stratified by vehicle availability level. The term "auto ownership" may be used interchangeably in this discussion, but the 1990 travel survey collected data on vehicles that were owned, leased or generally available for use by members of the household, so the accurate term to describe the information in this section is "vehicle availability." Five levels of vehicle availability are reported: none, one, two, three, and four-or-more vehicles in the household. Appendix Table 3.4.1A (trips per household) and Table 3.4.2A (trips per person) provide detailed trip rates by trip purpose and travel mode. The regional distribution of households and household population by vehicle availability level is shown below: Click HERE for graphic. Transit shares for home-based work and total trips by vehicle availability level are shown in Table 3.4.1 and Figure 3.4.1. Transit shares for work trips drops from 51.4 percent of zero- vehicle households to 2.9 percent of four-or-more vehicle households. Transit shares for total trips drops from 41.0 percent of zero-vehicle households to 2.0 percent of four-or-more vehicle households. Trips per household increases from 3.9 trips per weekday for zero-vehicle households to 12.3 trips per weekday for households with four-or-more vehicles. Home-based work total trips increases from 0.9 trips per weekday for zero-vehicles households to 3.7 trips per weekday for households with four-or-more vehicles. Transit trips per household decrease with increasing vehicle availability level, from 1.6 transit trips per weekday for zero- vehicle households to just 0.2 transit trips per weekday for households with four-or-more vehicles. -56- Zero-vehicle households account for 10.1 percent of the Bay Area's households and 7.1 percent of the Bay Area's household population, but they also account for 33.6 percent of the Bay Area's total transit trips (361,900 out of 1,076,200) and 22.6 percent of the Bay Area's home-based work transit trips (101,500 out of 449,400). Demographic characteristics of households by vehicle availability level are summarized in Table 3.4.2. Vehicle availability shows a positive correlation with household size and household income, and an inverse relationship to age. This means that zero-vehicle households tend to be more elderly and tend to be poorer than multiple-vehicle households. -57- Table 3.4.1 1990 Regional Transit Share for Trips per Household by Vehicle Availability Click HERE for graphic. -58- Figure 3.4.1 Regional Transit Shares by Vehicle Availability Click HERE for graphic. -59- Table 3.4.2 1990 Regional Household Characteristics by Vehicle Availability Click HERE for graphic. -60- 3.5 Regional Trip Rates by Housing Structure Type This section describes household trip rates stratified by housing structure type. The six categories of housing structure type collected in the 1990 household travel survey are: single- family, duplex, apartment, condominium/townhome, mobile home, and hotel/motel. Appendix Table 3.5.1A (trips per household) and Table 3.5.2A (trips per person) provide detailed trip rate data by trip purpose and travel mode. The regional distribution of households and household population by these six structure types is shown below: Click HERE for graphic. As can be seen in the above table, single-family dwelling units account for 61.2 percent of the weighted, expanded regional households and 69.0 percent of the regional household population. Household size for single-family dwelling units (2-95 persons per household) is significantly larger than the other housing structure types (1-94 to 2.50 persons per household). Household trip rates and transit share for home-based work and total trips, by housing structure type, is shown in Table 3.5. Household trip rates for work and total trips are highest for single-family dwelling units (8.6 trips per weekday), and lowest for apartment-dwelling households (5.5 trips per weekday). Transit shares are lowest for mobile home-based households (2.5%) and highest for apartment dwelling households (13.7%). -61- Table 3.5 1990 Regional Transit Share for Trips per Household by Structure Type Click HERE for graphic. -62- 3.6 Regional Trip Rates by County of Residence This section describes household trip rates stratified by nine Bay Area counties of residence. Appendix Table 3.6.1A (trips per household) and Table 3.6.2A (trips per person) provide detailed trip rates by county of residence by trip purpose and travel mode. The number of expanded survey households and household population, based on the expanded 1990 survey, is shown below: Click HERE for graphic. The total household and household population data should be very similar to 1990 Census data given that the 1990 household travel survey was weighted and expanded to the 1990 count of households by household size. Total trips per household ranges from a low of 6.6 trips per weekday for San Francisco households to 8.3 trips per weekday for Napa County households (Table 3-6). Contra Costa County (8.1 trips per household per weekday) and Sonoma County (8-0 trips per household per weekday) also have higher than average household trip rates. Alameda County households, at 7.2 trips per household, have the second lowest trip rates after San Francisco. Home-based work trips per household range from a low of 1.7 trips per weekday for -63- Sonoma County resident households to a high of 2.2 trips per weekday for Santa Clara County households. San Mateo County households also have higher than average home-based work trips per household (2.1 trips per weekday). The transit share for all trip purposes for residents of San Francisco County is 23.1 percent, significantly higher than the regional transit share of 6.3 percent. For home-based work trips, San Franciscans take transit 32.3 percent of the time, compared to the regional share of 10.0 percent. San Francisco, with 13.6 percent of the regional households and 11.9 percent of the regional household population, accounts for 40.4 percent of the regional home-based work transit trips and 43.1 percent o the regional total transit trips. Alameda County households have the second highest transit share for total trips in the region, at 7.4 percent of all trips. This is followed by San Mateo County (4.7 percent), Marin County (4-5 percent), and Contra Costa County (4.1 percent). The Bay Area counties with the lowest transit share of total trips include Napa County (1.1 percent), Solano County (1.7 percent) and Santa Clara County (2.0 percent). Work-trip transit shares are similar in ranking to total-trip transit shares. Alameda County workers take transit 13.0 percent of the time; Marin County, 9.1 percent; Contra Costa County, 8.4 percent; and San Mateo County resident workers, 7.6 percent of the time. Work-trip transit shares are lowest for residents of Sonoma County (1.8 percent), Napa County (2.3 percent), and Santa Clara County (2.5 percent). -64- Table 3.6 1990 Regional Transit Share for Trips per Household by County of Residence Click HERE for graphic. -65- 3.7 Regional Trip Rates by Workers in Household This section describes household and person trip rates stratified by the number of workers in the household. Trip rates are reported for four workers-in-household categories: none, one, two, and three-or-more workers. There are no appendix tables to supplement this section. The regional distribution of households and household population by the four workers-in-household categories is shown below: Click HERE for graphic. The above table shows a high correlation between household size and workers per household. It is also useful to indicate that 18.0 percent of Bay Area households have no workers (e.g., household comprises all retired or unemployed adults), and that 43.5 percent of all households in the Bay Area are multi-worker households. Total trips per household range from 4.4 trips per weekday for non-working households to 12.8 trips per weekday for multi-worker households with three-or-more workers (Table 3.7.1 and Figure 3.7.1). The survey results indicate that 3.0 percent of the trips made by households with no workers are home-based work trips. These trips are likely miscodes of trip purpose and are probably school trips or volunteer trips made by persons in these households. Analyzing the trip purpose share for non-working and working households is useful in understanding the travel behavior of Bay Area residents. For non-working households, the largest share of trips are home-based shopping trips at 45.3 percent of all trips (1.972 home-based shop trips per day of 4.354 total trips per day). For multi-worker households with three-or-more workers, the largest share of trips are home-based work trips at 37.6 percent of all trips (4.813 home-based work trips out of 12.811 total trips). Non- working households tend to be elderly/retired or -66- unemployed households with shopping as the principal out-of- home activity. Multi-worker households tend to have workers who commute a lot. Home-based school and non-home-based trips per household increases with. increasing number of workers in the household, yet home-based shop and home-based social/recreation trips per household show indefinite relationships with respect to workers in the household. Transit shares for total trips range from a low of 5.2 percent of trips for two-worker households to a high of 10.6 percent for no-worker households. The home-based work transit share for one- worker households (12.8 percent) is noticeably higher than the shares for two-worker (8.8 percent) and three-or-more worker (9.5 percent) households. There is a significant jump in trips per person when comparing non-working households (2.4 trips per weekday) to one-worker (3.0 trips) and multi-worker (2.9 to 3.0) households (Table 3.7.2). Total trips per person is virtually the same for the one worker and multi-worker household categories. On a trip purpose basis, however, home-based work trips increase with increasing number of workers-in-households, which is offset by decreases in home-based shop, home-based social/recreation, and non-home-based trips per person. -67- Table 3.7.1 1990 Regional Trips per Household by Workers in Household Click HERE for graphic. -68- Table 3.7.2 1990 Regional Trips per Person by Workers in Household Click HERE for graphic. -69- Figure 3.7.1 1990 Trips per Household by Workers in Household by Trip Purpose Click HERE for graphic. -70- 3.8 Regional Trip Rates by Household Life Cycle This section describes household and person trip rates stratified by household life cycle. The household life cycle categories used in this analysis are based on the categories used in the 1990 Nationwide Personal Transportation Study (NPTS). These are commonly used life cycle categories that were developed by travel behavior researchers in the 1970s and 1980s. Travel behavior researchers have used the household life cycle concept as an alternative means of segmenting households into relevant groupings for explaining and understanding travel behavior of families and households. This analysis is MTC's fir st attempt at analyzing household travel survey data using the household life cycle concept. A comparison of the distribution of households by household life cycle category based on the 1990 Bay Area travel survey and the 1990 NPTS is shown below: Click HERE for graphic. The largest household life cycle category in the Bay Area is the "two or more adults, no children" category with 26.1 percent of all regional households. This is followed by the "single adult, no children" category at 16.7 percent of all households; "two or more adults, youngest child under 6 years" category at 14.9 percent; and the "two or -71- more adults, youngest child 6 to 15 years" category at 13.3 percent of all households. The 1990 Bay Area travel survey analysis of households by life cycle category are quite similar to the 1990 NPTS distribution of households by these same categories. The distribution of 1990 Bay Area households, household population, total trips, total trips per household and total trips per capita is presented in Table 3.8.1. Mean household size ranges from 1.0 for the two sets of single adult categories to 4.39 persons per household for the "two or more adults, youngest child under 6 years" category. The "'two or more adults, youngest child 6 to 15 years" category has the next highest average household size at 4.33 persons per household. Trips per household range from a low of 2.7 trips per weekday for the single retired adult household to a high of 13.7 trips per weekday for the ",two or more adults, youngest child 6 to 15 years" category. The second highest trips per household rate is for the two or more adults, youngest child age 16 to 21 years" with an average of 11.9 trips per household per weekday. In contrast, trips per person range from a low of 1.5 trips per weekday for the "single adult, youngest child under 6 years" household category to a high of 4.0 trips per weekday for the single adult (not retired) household group. On a trips per person basis, the second most mobile group are the "two or more adults, no children" set of households at 3.3 trips per person per weekday. Trips per household by household life cycle category by trip purpose is highlighted in Table 3.8.2. Also shown are trip purpose shares. Home-based work shares range from 2.4 percent of the trips made by single retired adult households (most likely miscodes of trip purpose since these adults are reportedly retired) to 36.3 percent of all trips made by "two or more adults, no children" households. In terms of home-based work trips per household, the "two or more adults, youngest child 16 to 21 years" has the highest trip rate at 3.6 trips per household per weekday. Home-based shop trip shares range from 18.5 percent of trips made by "single adult, youngest child 16 to 21 years" households to 50.5 percent of trips made by retired single adult households. These retired single adult households also have the highest share of home-based social/recreation trips (18.0 percent). Home-based school trips account for 24.7 percent of the trips mad by "single adult, youngest child 6 to 15 years" households, followed for 20.0 percent of the trips made by "two or more adults, youngest child 6 to 15 years" households. -72- Table 3.8.1 1990 Regional Trips per Household and per Person by Household Life Cycle (Nationwide Personal Transportation Survey (NPTS) Categories) Click HERE for graphic. -73- Table 3.8.2 1990 Regional Trips per Household by Trip Purpose by Household Life Cycle (Nationwide Personal Transportation Survey (NPTS) Categories) Click HERE for graphic. -74- 3.9 Regional Trip Rates by Household Size by Vehicle Available This section describes household and person trip rates, by trip purpose, cross-classified by household size and vehicle availability. Five household size groups are used in this analysis (one, two, three, four, and five-or-more persons) and four vehicle availability categories are used (none, one, two, and three-or-more vehicles). Trips per household are summarized in Table 3.9.1. Trips per person are shown in Table 3.9.2. The number of sample households, expanded households, and expanded household population is reported in Table 3.9.3. Several cells in this cross-classification matrix have an insufficient number of household samples to be considered statistically valid. These are the zero-vehicle households with four or five-or-more persons per household categories. The trip rate information is provided for information purposes only. The largest category in this cross-classification matrix is the two-person, two-vehicle household with 373,000 households out of 2.25 million regional households. This is followed by the one- person, one-vehicle household category with 369,000 households. Total trips per household show increases in both dimensions of this cross-classification matrix, that is, trips per household increases with increasing number of vehicles per household and increasing number of persons per household. The one-person household with no vehicles makes an average of 2.7 trips per household per weekday. The household with five-or-more persons and three-or-more vehicles makes an average of 16.3 trips per household per weekday. This pattern of increasing trips per household is less pronounced and more varied on a trip purpose basis, with some trips per household decreasing with increasing number of vehicles per household. Trips per person show an increase with more vehicles per household and a decrease with more persons per household. The most mobile bunch of households are the one-person households with three-or-more vehicles (0.8 percent of all households) who make 4.2 trips per average weekday. The least mobile households are the households with five-or-more persons and only one vehicle available (1.8 trips per person per weekday). -75- Table 3.9.1 1990 Regional Trips per Household by Household Size by Vehicles Available per Household - Total Modes Click HERE for graphic. + Trip rates based on less than 50 sample households and are not statistically significant. Reported for information purposes only. -76- Table 3.9.2 1990 Regional Trips per Person by Household Size by Vehicles Available per Household - Total Modes Click HERE for graphic. + Trip rates based on less than 50 sample households and are not statistically significant. Reported for information purposes only. -77- Table 3.9.3 1990 Households and Household Population by Household Size by Vehicles Available per Household 1990 MTC Household Travel Survey - Single Day Sample Click HERE for graphic. -78- 3.10 Regional Trip Rates by Household Size by Workers in Household This section describes household and person trip rates, by trip purpose, cross-classified by household size and workers in the household. Five household size groups are used in this analysis (one, two, three, four, and five-or-more persons) and four workers in household categories are used (none, one, two, and three-or-more workers). Trips per household are summarized in Table 3.10.1. Trips per person are shown in Table 3.10.2. The number of sample households, expanded households, and expanded household population is reported in Table 3.10.3. Several cells in this cross-classification matrix have an insufficient number of household samples to be considered statistically valid. These are the zero-worker households with four or five-or-more persons per household categories. The trip rate information is provided for information purposes only. Three other categories are not included in the cross-classification due to impossible combinations: two workers in a one-person household; and three-or-more workers in a one-person or a two-person household. The largest category in this cross-classification matrix is the one-person, one-worker household with 391,000 households out of 2.25 million regional households. This is followed by the two- person, two-vehicle household category with 363,000 households. Total trips per household show increases in both dimensions of this cross-classification matrix, that is, trips per household increases with increasing number of workers per household and increasing number of persons per household. The one-person household with no workers makes an average of 2.8 trips per household per weekday. The household with five-or-more persons and three-or-more workers makes an average of 15.1 trips per household per weekday. Trips per person show an increase with more workers per household and a decrease with more persons per household. The most mobile households are the one-person, one-vehicle households who make 4.1 trips per average weekday. The least mobile households (on a per capita basis) are the households with five-or-more persons and only one vehicle available (2.3 trips per person per weekday). -79- Table 3.10.1 1990 Regional Trips per Household by Household Size by Workers per Household - Total Modes Click HERE for graphic. + Trip rates based on less than 50 sample households and are not statistically significant. Reported for information purposes only. -80- Table 3.10.2 1990 Regional Trips per Person by Household Size by Workers per Household - Total Modes Click HERE for graphic. + Trip rates based on less than 50 sample households and are not statistically significant. Reported for information purposes only. -81- Table 3.10.3 1990 Households and Household Population by Household Size by Workers per Household 1990 MTC Household Travel Survey - Single Day Sample Click HERE for graphic. -82- 3.11 Regional Trip Rates by Workers in Household by Vehicles available This section describes household and person trip rates, by trip purpose, cross-classified by workers in the household and by vehicle available. Four workers in household groups are used in this analysis (none, one, two, and three-or-more workers) and four vehicle categories are used (none, one, two, and three-or-more vehicles). This is the third and final set of two-way cross- classification analyses using household size, vehicles available, and workers in household categories. Trips per household are summarized in Table 3.11.1. Trips per person are shown in Table 3.11.2. The number of sample households, expanded households, and expanded household population is reported in Table 3.11.3. The cell with three-or-more workers and zero-vehicles available in this cross-classification matrix has an insufficient number of household samples to be considered statistically valid. Trip rate information is provided for information purposes only. The largest category in this cross-classification matrix is the two-worker, two-vehicle household with 444,000 households out of 2.25 million regional households. This is followed by the one- worker, one-vehicle household category with 411,000 households. Total trips per household show increases in both dimensions of this cross-classification matrix, that is, trips per household increases with increasing number of workers per household and increasing number of vehicles per household. The non-working household with no vehicles makes an average of 3.0 trips per household per weekday. The household with three-or-more workers and three-or-more vehicles makes an average of 13.7 trips per household per weekday. Trips per person tend to increase with more workers and more vehicles per household, though there are several exceptions to this tendency. In terms of trips per capita, the most mobile households are the two-worker households with three-or-more vehicles (3-1 trips per person per weekday). The least mobile households (on a per capita basis) are the non-working households with no vehicles available (1.7 trips per person per weekday). -83- Table 3.11.1 1990 Regional Trips per Household by Workers per Household by Vehicles Available per Household - Total Modes Click HERE for graphic. + Trip rates based on less than 50 sample households and are not statistically significant. Reported for information purposes only. -84- Table 3.11.2 1990 Regional Trips per Person by Workers per Household by Vehicles Available per Household - Total Modes Click HERE for graphic. + Trip rates based on less than 50 sample households and are not statistically significant. Reported for information purposes only. -85- Table 3.11.3 1990 Households and Household Population by Workers per Household by Vehicles Available per Household 1990 MTC Household Travel Survey - Sin e Da Sample Click HERE for graphic. -86- 3.12 Regional Trip Rates by Density Based Area Type This last section on trip rates reports on household and person trip rates stratified by density-based area. There are six "area type" categories used in the Bay Area, which are based on a combination of net employment and net population density. The "area type density" is calculated as follows: Area Type Density = (Total Population + 2.5 * Total Employment) / Developed Acres Characteristics of the Bay Area by these six area types is shown below: Click HERE for graphic. The regional "core" includes the heart of downtown San Francisco and Oakland, and account for 8.8 percent of the region's total employment in 1990. The "central business district" encompasses the ring around the core downtown in San Francisco and Oakland, and the downtown areas of Berkeley, San Jose and Concord. The "urban business district" includes the ring around San Francisco, Oakland, Daly City, Walnut Creek, Santa Rosa, Palo Alto, Hayward, San Jose, and the "Golden Triangle" area of "Silicon Valley" in Santa Clara County. The term "urban" encompasses the remainder of San Francisco, most of Oakland, Berkeley, and Silicon Valley. The "suburban" area of the Bay Area is the largest area type, comprising 64.2 percent of the land area and 39.5 percent of the total employment in the region. "Rural" areas can be found in all counties except San Francisco. A wall map showing these area types is on display in MTC offices. Additionally, MTC's computerized highway networks use the "area type" designation in traffic analysis, and on-screen viewing of the Bay Area street and road network is the best way to understand the geographic extent of the different density-based area types used in MTC's planning analyses. -87- The regional distribution of households and household population by the six area types is shown below: Click HERE for graphic. Note that the Bay Area suburban areas account for about two- thirds of the households and population in the region. Note also that mean household size decreases with increasing density, except for rural areas which show slightly lower average household sizes that suburban areas. Appendix Tables 3.12.1A (trips per household) and 3.12.2A (trips per person) show detailed trip rates by area type by trip purpose and travel mode. Three additional tables are included that show home-based work and total trip transit shares, walk shares, and bicycle shares by area type. Trips per household decrease with increased density (Table 3.12.1). The trips per household for residents of the regional core area average 4.0 trips per weekday; in suburban areas, 8.0 trips per weekday; and in rural areas, 9.1 trips per weekday. Home-based work trips also increase with lower densities, rising from 1.2 home-based work trips per household for residents of the regional core to 2.1 home-based work trips per suburban household. Rural households tend to have lower home-based work trip rates (1.7) than residents of other areas (due to either higher tendency to work at home or higher number of retired households). The transit shares for total trips show a high correlation with density-based area types. Transit shares in the regional "core" area are 30.0 percent of total trips; for suburban areas, transit shares are 3.4 percent of total trips. For home-based work trips, transit shares peak at 38.1 percent of trips made by residents of the regional -88- "core" and average at 5.9 percent for residents of suburban areas and 2.6 percent of rural areas. Note that there is a high degree of correlation between area type and other, more behavioral characteristics of households, namely, household size, workers per household and household income. The intention here is show the correlation between density and transit shares, not to imply causality in terms of how higher density neighborhoods 'cause" more people to ride transit. A thorough statistical analysis is needed to distinguish the importance of density relative to other household characteristics (e.g., household size, income, workers per household) in terms of causing people to ride transit. Walk share of total trips is also highly and positively correlated with density (Table 3.12.2). The walk share of total trips in the regional core of the Bay Area is 34.8 percent; for suburban areas, 7.8 percent of all trips are by walk. Home-based work walk shares range from a high of 29.0 percent in the regional core to 1.5 percent for residents of rural areas. Bicycle share of total trips also appears to be positively correlated with density (Table 3.12.3). Bicycle share for residents of regional core neighborhoods is 4.0 percent of total trips; for residents of suburban areas, 1.4 percent. Residents of "central business districts" show a low tendency to use bicycles, at 0.8 percent of all trips, though residents of the next lower density group, "urban business district," show a higher bicycle share at 2.7 percent of total trips. -89- Table 3.12.1 1990 Regional Transit Share for Trips per Household by Area Type Click HERE for graphic. -90- Table 3.12.2 1990 Regional Walk Share for Trips per Household by Area Type Click HERE for graphic. -91- Table 3.12.3 1990 Regional Bicycle Share for Trips per Household by Area Type Click HERE for graphic. -92- 4.0 Weekday 1990 Travel by Personal Characteristics Section 4.0 of Working Paper #4 discusses travel patterns based on the personal characteristics of individual travelers. The previous section dealt with travel patterns based on household characteristics such as income, household size, workers in the household, vehicles available, etc. This section describes travel based on personal characteristics such as age, gender, employment status, drivers license status, and disability status. 4.1 Travel by Age of Person This subsection reports on trips per person by age of the survey respondent. Data is taken from the weighted, expanded 1990 travel survey "single day" sample. Trips per person and share of trips by trip purpose by detailed age categories is shown in Table 4.1.1. Trips per person by detailed age is charted in Figure 4.1.1. Note the parabolic shape of the trips per person distribution in this chart, peaking at 4.31 trips per person for 41-years-old, and showing less trips per capita for younger as well as older persons. The least mobile group, on a trips per capita basis, are Bay Area residents 75 years and over with just 2.18 trips per person per weekday. The cumulative frequency distribution of trips by trip purpose share by detailed age category is charted in Figure 4.1.2. This chart illustrates the high share of home-based school trips made by persons age 5 to 18; the high share of home-based work trips made by persons age 22 through 65; and the high share of home-based shop (other) trips made by persons age 65 and over. The transitional years between the ages of 18 and 22 show a dramatic changeover from a predominance of home-based school trips to home-based work trips. Home-based social/recreation trips tend to have the highest shares for the younger (less than 20 years) and the older (greater than 64 years) residents. Non-home-based trip share of total trips tends to increase with age. The share of home-based school trips of total trips declines rapidly after persons reach their early 20s. Home-based work trip share of total trips peaks at 40.0 percent of all trips made by 24-years-old. The detailed age categories presented in Table 4.1.1 are collapsed into eight categories in Table 4.1.2. This helps in comprehending general person trip rate and trip purpose share patterns by age group. Trips per person range from a low of 2.48 trips for persons age 65 and over to a high of 3.74 trips for persons in their 40s. Children -93- age 5 to 17 are the second least "mobile" group at only 2.60 trips per person per weekday. The second highest mobile group are 30-years-old, averaging 3.56 trips per person per weekday. Trip purpose share data is presented in Table 4.1.2 and Figure 4.1-3. Home-based work share of total trips range from a low of 2.4 percent of trips made by children age 5 to 17 to a high of 37.2 percent of trips made by residents age 23 to 29. Home-based school share of total trips decreases with increasing age group, peaking at 46.9 percent of the trips made by children age 5 to 17, and less than one percent of the trips made by residents age 60 and over. The home-based shop share of total trips tends to increase with increasing age. Only 18.4 percent of the trips for children age 5 to 17 are home-based shop trips contrasting with 47.2 percent of the trips made by residents age 65 and over. Home-based social/recreation trip share of total trips is highest for the 65 and over category, at 16.9 percent; and lowest for persons age 40 to 49, at just 8.6 percent of all trips. Non-home-based share of total trips also tends to increase with increasing age, up to the 40s. As people get older than 50, non-home-based share of total trips tends to decrease. Modal share for home-based work and total trips by these sight age groups are shown in Table 4.1.3. Walk mode shares for total trips are highest for the very young (19.0 percent) and the eldest group (12.5 percent). Walk mode shares are the lowest for residents age 40 to 49 (6.9 percent). Bicycle mode shares for total trips are highest for the youngest group (4.2 percent) and lowest for the eldest group (0.2 percent). Transit mode shares are highest for 18-to-22-year-old residents (8-6 percent) and lowest for 60-to-64-year-old residents (4.9 percent). Vehicle driver shares are highest for the 40-to-49-year-old residents (78.7 percent) and lowest for the youngest group (8.5 percent). -94- Table 4.1.1 Average Trips per Person and Trip Purpose Share by Age of Trip Maker Click HERE for graphic. -95- Table 4.1.1 (continued) Average Trips per Person and Trip Purpose Share by Age of Trip Maker Click HERE for graphic. -96- Figure 4.1.1 Average Total Trips per Person by Age of Trip Maker Click HERE for graphic. -97- Figure 4.1.2 Share of Trips by Trip Purpose by Age of Trip Maker Click HERE for graphic. -98- Table 4.1.2 Average Trips per Person and Trip Purpose Share by Age Group Click HERE for graphic. -99- Figure 4.1.3 Share of Trips by Trip Purpose by Age Group Click HERE for graphic. -100- Table 4.1.3 Modal Share for Work and Total Trips by Age Group Click HERE for graphic. -101- 4.2 Travel by Age and Gender of Person Section 4.2 of this working paper further breaks down the travel characteristics of Bay Area residents by gender as well as age group. Data as reported is from the weighted and expanded single day sample of the 1990 household travel survey. One important measure of overall personal mobility is the share of persons reporting travel (that they made trips) on their assigned travel day. People either travel or don't travel on any given day. The share that are traveling on any given day is the "mobile share" of the population, or the ones partaking in non-home activities. The mobile share of the population, comparing the San Francisco Bay Area with the Sydney and Melbourne, Australia metropolitan areas, is shown in Table 4.2.1. The Sydney data is derived from the 1981 Sydney metropolitan area household travel survey; the Melbourne data from the 1978/79 Melbourne metropolitan area survey. (Source: Marcus R. Wigan Australian Personal Travel Characteristics, Australian Road Research Board Special Report No. 38, 1987). The data for the three metropolitan areas show similar patterns. The most mobile persons are children age 5 to 11; the least mobile are persons age 65 and over. Males are typically more mobile than females, though the male/female differences are more pronounced at older age groups (i.e., 60 and over). : Overall, 83 percent of Bay Area residents reported travel on their assigned travel days. This compares to 78 percent of Sydney metropolitan area residents and 85 percent of Melbourne metropolitan area residents. In the Bay Area, 85.4 percent of males and 81.7 percent of females reported that they traveled out- of-home on their assigned travel day. This compares with 80 percent male, 76 percent female mobility in the Sydney region; and 90 percent male, 80 percent female mobility in the Melbourne region. The least mobile.group are residents age 65 and over. The Bay Area survey shows that 70.4 percent of men and just 60.3 percent of women age 65 and over partook in out-of-home activities on their assigned travel days. The Sydney and Melbourne data show similar low mobility levels for persons 65 and over. The other characteristics of personal mobility, as used in this working paper, is the number of trips per person by gender and age group. The total number of trips per capita and the trip purpose shares, by gender and age group, are shown in Table 4.2.2. As shown in section 4.1, the most mobile groups (in terms of trips per capita) are -102- middle-age persons age 40 to 49; the least mobile, persons age 65 and over. Trips per capita by gender of respondent shows no statistically significant difference for all persons age 5 and over. Males reported an average of 3.203 trips per person per weekday; females reported 3.209 trips per person per weekday. On an age group basis, however, females tend to be more mobile than males during the early years of life (ages 5 through 49); males tend to be more mobile than females during the latter years of life (50 years and over). It is uncertain whether any of these differences in trips per capita by age group and by gender are statistically significant, though the numerically largest difference is for persons age 65 and over, where men take an average of 2.74 trips per person and women take an average of 2.30 trips per person per weekday. Trip purpose share by gender of traveler is shown in Table 4.2.2. The most notable difference between males and females, for all age groups combined, is for home-based work and home-based shop trips. The survey shows that 30.3 percent of all male trips and 22.6 percent of all female trips are for home-based work trip purposes. In contrast, 19.9 percent of all male trips and 29.9 percent of all female trips are for home-based shop (other) trip purposes. This reflects the higher labor force participation rate among males, and the higher likelihood of females performing the shopping and personal business chores for the average household. These male/female tendencies for work and shopping trip shares are consistent across all age groups, except for a statistically insignificant difference for work trip share for children age 5 to 17. The last table in this section looks at modal shares for work and total trips, by gender and age group (Table 4.2.3). The survey shows that females are more likely than men to take public transit, walk, or be a passenger in a vehicle. Males are more likely to be a vehicle driver or ride a bicycle. Males' vehicle driver share for all trips is 67.5 percent; females, 61.3 percent. Males' vehicle passenger share for all trips is 13.6 percent; females, 19.5 percent. Males' transit share for all trips is 5.8 percent; females, 6.6 percent. Males' bicycle share for all trips is 2.2 percent; females, 0.8 percent. Males' walk share for all trips is 9.4 percent; females, 10.4 percent. The modal share patterns by gender and age group, shown in Table 4.2.3, are similar to the patterns discussed for Table 4.1.3. Males show consistently higher vehicle driver and bicycle rider shares than females across all age groups. Females show consistently higher vehicle passenger and transit passenger shares than males across all age groups. Females tend to have higher walk shares than males, except for the 5- -103- to-17-year-old group, where boys (21.2 percent of all trips) have a higher share of walk trips than girls (16.8 percent of all trips). The work trip modal shares for males and females by age group follow the same pattern as total trip modal shares, with a few exceptions. Young male workers under age 18 have higher work trip transit shares than young female workers (8.9 percent male versus 4.4 percent female). Also, elderly male workers (65 and over) have higher work trip transit shares than elderly female workers (15.8 percent male versus 14.7 percent female). These very young and very elderly workers are very small markets of total home-based work trips. Overall, the home-based work transit share for females (12.2 percent) is significantly higher than the home-based work transit share for males (8.4 percent). -104- Table 4.2.1 Share of Population Reporting Travel by Age and Gender 1990 San Francisco Bay Area, 1981 Sydney, and 1978/79 Melbourne Click HERE for graphic. -105- Table 4.2.2 Average Trips / Person and Trip Purpose Share by Age Group by Gender Click HERE for graphic. -106- Table 4.2.3 Modal Share for Work and Total Trips by Age Group by Gender Click HERE for graphic. -107- 4.3 Travel by Employment Status Section 4.3 of this working paper discusses travel characteristics stratified by employed and not-employed persons. This includes a discussion of average weekday trip rates per person, trip purpose shares, and modal shares. The following table shows the distribution of weighted and expanded persons (age 5 and over) by employment status by gender-. Click HERE for graphic. The survey shows that 58.4 percent of Bay Area residents age five and over are employed persons. By gender, 64.6 percent of males and 52.4 percent of females are employed. The majority (54.1 percent) of workers are males; the majority of nonworkers (58.5 percent) are females. Trips per person and trip purpose share, by gender and employment status, are shown in Table 4.3.1. The survey shows a small number of home-based work trips made by nonworkers. This may be due to the miscoding of the employment status of the person in question, or may be due to the miscoding of volunteer or school trips as "work" trips. Note that "non-employed" persons includes persons without formal jobs, including student, retired, unemployed, and homemaker occupations. (If a person claimed more than one "status,", say, being a student and a part-time worker, or being retired and a part-time worker, then that person was classified as an employed person.) Trips per person are significantly higher for employed persons as opposed to nonemployed persons. Employed males take an average of 3.51 trips per day; nonemployed males, 2.64 trips per day. Employed females take an average of 3.61 trips per day; non- employed females, 2.77 trips per day. An interesting observation is that employed females take more trips per day than employed males; non-employed females also take more trips per day than non- employed males. The plurality of trips made by employed persons are home-based work trips. For -108- male employed persons, 41.2 percent of all trips are home- based work trips. For females, 36.2 percent of all trips are home- based trips. Note that the share of home-based shop trips for employed females (22.8 percent) is substantially higher than the share of home-based shop trips made by employed males (16.2 percent). The plurality of trips made by non-working males are home- based school trips (30.0 percent of all trips). The plurality of trips made by non-working females are home-based shop trips (40.1 percent of all trips). Modal share for home-based work and total trips, by employment status and by gender, is shown in Table 4.3.2. In terms of modal shares for total trips, non-workers tend to have significantly higher vehicle passenger, bicycle and walk shares as compared to workers; and significantly lower vehicle driver shares as compared to employed persons. Interestingly enough, the transit share for non-workers is not significantly higher for non-workers as compared to workers. Non-working females take transit 6.6 percent of the time. Working females take transit for 6.5 percent of all trips. Non-working males take transit for 7.0 percent of all trips. Working males take transit for 5.3 percent of all trips. (Any further extension to this analysis will require the review of trip rates, trip purpose and modal shares cross- classified by employment status, gender, and age of person. It is evident from the analysis at hand that all three demographic variables - age, gender, and employment status - are important characteristics, or determinants, of personal travel patterns.) -109- Table 4.3.1 Average Trips per Person and Trip Purpose Share by Employment Status by Gender Click HERE for graphic. * Work trips made by non-employed persons may be due to miscoding of person by employment status, or due to miscoding volunteer, school, etc., trips as work trips. -110- Table 43.2 Modal Share for Work and Total Trips by Employment Status by Gender Click HERE for graphic. -111- 4.4 Travel by Driver's License Status Section 4.4 of this working paper discusses per capita trip rates, trip purpose shares, and modal shares stratified by persons with and without a driver's license. Data is also summarized on the number of persons by age and by gender, with and without a drivers license. Persons with a driver's license have significantly higher trips per capita than persons without a drivers license (Table 4.4- 1). Males with a drivers license make an average of 3.40 trips per person per weekday; males without, 2.35 trips per person. Females with a drivers license make an average of 3.54 trips per person per weekday; females without, 1.95 trips per person per weekday. The trip purpose share for persons with a drivers license are more oriented toward home-based work and non-home-based trips. Persons without a drivers license have a higher share of home-based shop and home-based school trips. Regionally, 74.8 percent of the Bay Area population age five or more has a driver's license (Table 4.4.2). This varies from 72.3 percent of females with a license to 77.5 percent of males. The age distribution of persons with and without a driver's license shows that the majority (64.7 percent) of the non-drivers are children age 5 to 17. Only 7.3 percent of the children age 5 to 17 have a drivers license. The second lowest age group, in terms of share of population with a drivers license, is the 65 and over group, with just 72.7 percent having a license. Note the very low share of women age 65-and-over with a driver's license (63.6 percent). The vast majority of men age 30 to 59 have a drivers license (95 percent to 97 percent). For women, the age group with the highest share with a license is 30 to 39 (92.6 percent). Modal share data for males and females with and without a drivers license, for home-based work and total trips, is shown in Table 4.4.3. Note the small share (and numbers) of vehicle driver trips made by non-drivers. These discrepancies are due to a likely miscoding of either driver's license status or mode of travel. The majority of trips made by non-drivers are as vehicle passengers. Non-drivers also take proportionately more transit, bicycle and walk trips as compared to drivers. -112- Table 4.4.1 Average Trips / Person and Trip Purpose Share by Driver's License by Gender Click HERE for graphic. -113- Table 4.4.2 Characteristics of Persons by Driver's License, Age and Gender Click HERE for graphic. -114- Table 4.4.3 Modal Share for Work and Total Trips by Driver's License by Gender Click HERE for graphic. * Vehicle driver trips made by persons without a driver's license are a probable miscoding of either driver's license status or mode of travel. -115- 4.5 Travel by Disability Status This section discusses the per capita trip rates, trip purpose shares and modal shares of persons stratified by those with and without a disability. As defined in the 1990 survey, disability, more precisely "public transportation disability," was based on the question: "Does anyone in your household have any physical, mental or other health condition which has lasted six months or more and which makes it difficult to use public transportation?" The following table shows the survey-expanded distribution of the Bay Area population, age five and over, by gender, stratified by public transportation disability status: Click HERE for graphic. Of the 21,300 persons age five and over sampled in the 1990 "single day sample" household travel survey, just 389 reported having a public transportation disability. While this is a large enough sample to provide some comfortable statistical estimates, the concern is that this share of persons with a public transportation disability (1-9 percent) compares poorly with the 1990 Census estimate of persons with a mobility limitation (9.7 percent of the population age 16 and over). This under representation of disabled in the 1990 survey is probably due to different (and difficult to understand) wording of the question on public transportation disability. Disabled persons have significantly lower daily trips per person than non-disabled persons (Table 4.5.1). Males with a public transportation disability take, on average, 2.12 trips per day; males without a disability, 3.22 trips per day. Females with a disability take an average of 2.17 trips per person per weekday; females without a disability, 3.23 trip per day. In terms of trip purpose share, persons with disabilities have a proportionately higher share of home-based shop trips than persons without disabilities. Persons with disabilities have lower share of home-based work and home-based school trips -116- than persons without disabilities. There does not appear to be a major difference in trip purpose share in terms of home-based social/recreation or non-home-based trips made by disabled versus non-disabled persons. Disabled versus non-disabled person modal shares for total and home-based work trips is presented in Table 4.5.2. On a total trip basis, disabled persons have a slightly higher likelihood of taking transit or being a vehicle passenger, compared to non-disabled persons. Disabled persons have a lower share of vehicle driver and bicycle trips as compared to non-disabled persons. These differences are more distinct for home-based work trips. The work trip transit share for disabled persons (20.1 percent) is twice as high than for non-disabled persons (10.0 percent). Vehicle passenger and walk shares are higher for the disabled worker as compared to the non-disabled worker. Vehicle driver and bicycle shares are lower for the disabled worker as compared to the non-disabled worker. -117- Table 4.5.1 Average Trips per Person and Trip Purpose Share by Disability Status by Gender Click HERE for graphic. -118- Table 4.5.2 Modal Share for Work and Total Trips by Disability Status by Gender Click HERE for graphic. -119- 5.0 Weekday 1990 County Travel Section 5.0 of Working Paper #4 discusses county-level travel patterns. Data is reported from the expanded, weighted "single day sample" survey. Tables included in Appendix 5.0 show detailed county-to-county trip tables by trip purpose and travel mode. 5.1 County Trips by Trip Purpose This subsection discusses county-level trip productions and trip attractions by trip purpose. The term "production" and "attraction" are terms commonly used in transportation planning analysis. "Productions" are always the home-end of all home-based trips. "Attractions" are always the non-home-end of all home-based trips. For non-home-based trips, the trip origin is the same as the trip production; the trip destination is the same as the trip attraction. Weekday trips by trip purpose and county of production are shown in Table 5.1.1. The largest number of trips are produced in Santa Clara County (4.08 million trips per weekday); the smallest number, in Napa county (344,000 trips per weekday). By trip purpose share, Napa County residents have the lowest share of home- based work trips (21.2 percent) compared to San Mateo County with the highest share of home-based work trips (29.4 percent). Home-based shop (other) trip purpose shares range from a low of 20.7 percent of trips made by San Francisco residents to 30.4 percent of trips made by Solano County residents. Home-based social/recreation trip purpose shares range from 9.0 percent of Alameda County residents' trips to 13.0 percent of San Mateo County residents' trips. Residents of Marin County (7.9 percent) have the lowest home- based school trip purpose sharer Solano County (11.6 percent), the highest. Non-home-based trips range from a low of 22.2 percent of the trips produced in Solano County to 35.2 percent of the trips produced in San Francisco County. Weekday trips by trip purpose and county of attraction are shown in Table 5.1.2. Again, Santa Clara County attracts the largest share of the regional number of total trips (4.17 million trips out of 16.97 million); Napa County, the smallest share (340,300 trips). -120- The trip purpose share for home-based work trips varies by county, from a low of 19.3 percent of the trips attracted to Sonoma County, to a high of 32.1 percent of the trips attracted to San Francisco County. Home-based shop attraction county shares range from 19.4 percent of the total trips attracted in San Francisco to 32.5 percent of the trips attracted to Solano County. Home-based social/recreation trip purpose shares range from 9.1 percent of Alameda County attractions to 13.6 percent of Marin County attractions. Home-based school trip purpose shares range from just 7.9 percent of Marin County attractions to 11.4 percent of Solano County attractions. Non-home-based trip purpose shares range from a low of 24.2 percent in Solano County to a high of 32.6 percent of the trips attracted to Marin County. -121- Table 5.1.1 1990 Weekday Trips by Trip Purpose and County of Production Click HERE for graphic. Notes: Upper entry is the number of trips. Lower entry is the row percent. -122- Table 5.1.2 1990 Weekday Trips by Trip Purpose and County of Attraction Click HERE for graphic. Notes: Upper entry is the number of trips. Lower entry is the row percent. -123- 5.2 County Trips by Travel Mode This subsection reports on the number and share of county- level trips by travel mode, by county of production and county of attraction. Home-based work trips by mode by county of production are shown in Table 5.2.1. Home-based work trips by mode by county of attraction are shown in Table 5.2.2. Transit shares for home-based work trips, by county of production, range from a low of 1.9 percent of Sonoma County work trip productions to 32.4 percent of San Francisco County resident work trip productions. San Francisco resident workers account for 40.3 percent of the regional work trip productions. Alameda County has the next highest work trip transit share, at 13.0 percent, followed by Marin County, 9.3 percent, Contra Costa County, 8.5 percent; and San Mateo County, 7.7 percent. Walk shares for home-based work trips range from 1.4 percent of Contra Costa County productions to 7.2 percent of San Francisco County productions. San Francisco resident workers account for 29.9 percent of the regional home-based work trips via walking. Bicycle shares for home-based work trip productions range from a low of 0.3 percent of Contra Costa trips to 1.4 percent of Alameda County work trips. Santa Clara County has the largest number (16,700) home-based work trip productions taken on bicycle. Vehicle passenger shares for home-based work trip productions range from 6.1 percent in Sonoma County to 10.0 percent of Solano County productions. Vehicle driver shares for home-based work productions range from just 48.8 percent of San Francisco County work trips to 87.6 percent of Santa Clara County work trips. Santa Clara County resident workers account for 29.3 percent of the regional home-based work vehicle driver trips. The county of attraction (county of work) modal shares follow similar patterns to the county of production data (Table 5.2.2). Transit shares are highest to San Francisco County jobs at 38.5 percent of home-based work trips attracted. San Francisco jobs attract 68.8 percent (310,900 out of 451,800) regional home-based work transit trips. Home-based work walk trips (5.2 percent) and home-based work vehicle passenger trips (11.1 percent) are also the highest in San Francisco County. Home-based work bicycle trip shares are highest in Alameda (1.6 percent) and Santa -124- Clara (1-5 percent) counties. Vehicle driver home-based work shares range from a low of 43.6 percent to jobs in San Francisco County to a high of 89.6 percent of the work trips attracted to jobs in Sonoma County. A county-level comparison of 1990 household travel survey work trip shares to the 1990 Census (journey-to-work data) means of transportation-to-work shares is shown in Table 5.2.3. For this analysis, home-to-work related and work related-to-home trips were removed to be as comparable as possible to the Census definition of home-to-work commute travel. On a regional basis, the MTC 1990 Survey compares quite well with the modal shares from the 1990 Census. The survey slightly overestimates the number of transit work trips (10.5 percent survey versus 9.9 percent Census); and underestimates the share of walk work trips (3.1 percent survey versus 3.8 percent Census). These regional-level results are very encouraging. By county of residence, the work trip transit shares from the 1990 survey compare quite favorably with the 1990 Census. Alameda County shows the largest overestimate of transit work trips (13.6 percent survey versus 10.4 percent Census). Marin County shows the largest underestimate of transit work trips (9.6 percent survey versus 11.0 percent Census). Comparisons for other work trip travel modes, survey to census, are also quite favorable, with a few exceptions, including walk trips in San Francisco (7.2 percent survey versus 10.2 percent Census); and Marin County vehicle driver trips (81.0 percent survey versus 76.8 percent Census). Overall, the county-level comparison of work trip modal shares, survey shares relative to the 1990 Census, are quite acceptable. Modal shares for all trip purposes combined, by county of production, are shown in Table 5.2.4. Transit shares range from 1.0 percent of Napa County productions to 22.3 percent of San Francisco County productions. San Francisco County accounts for 46.2 percent of the regional transit trip productions. Alameda County has the second highest transit share, 7.0 percent; followed by San Mateo, 4.5 percent; Marin County, 4.3 percent; and Contra Costa County, 4.0 percent of all trips. Walk shares range from a low of 5.7 percent of all trips produced in Contra Costa County to 23.2 percent of all trips produced in San Francisco County. Bicycle shares range from a low of 0.5 percent of Contra Costa County trips to 1.9 percent of Napa and Sonoma County trips. Three other counties - Marin, San Mateo and Santa -125- Clara - have a 1.8 percent bicycle mode share. Vehicle passenger shares range from just 10.9 percent of the trips produced in San Francisco County to 19.1 percent of the trips produced in Solano County. Vehicle driver shares range from 41.4 percent of San Francisco trips to 73.1 percent of Marin county trips. Modal shares for all trip purposes by county of attraction are shown in Table 5.2-5. As with the previous analysis, San Francisco County leads in terms of transit passenger and walk share, and also has the lowest vehicle driver and vehicle passenger shares. San Francisco County accounts for 60.9 percent of the regional transit trip attractions (644,100 out of 1.06 million regional transit trips). -126- Table 5.2.1 1990 Weekday Home-Based Work Trips by Mode and County of Production Click HERE for graphic. Notes: Upper entry is the number of trips. Lower entry is the row percent. -127- Table 5.2.2 1990 Weekday Home-Based Work Trips by Mode and County of Attraction Click HERE for graphic. Notes: Upper entry is the number of trips. Lower entry is the row percent. -128- Table 5.2.3 Comparison of 1990 Census and 1990 Survey Modal Shares Work Trips by County of Residence Click HERE for graphic. Notes: Upper entry is 1990 Census modal share to work (travelers). Lower entry is 1990 Survey modal share for Census-comparable trips. -129- Table 5.2.4 1990 Weekday Total Trips by Mode and County of Production Click HERE for graphic. Notes: Upper entry is the number of trips. Lower entry is the row percent. -130- Table 5.2.5 1990 Weekday Total Trips by Mode and County of Attraction Click HERE for graphic. Notes: Upper entry is the number of trips. Lower entry is the row percent. -131- 5.3 County-to-County Trips This subsection of Working Paper #4 discusses the county-to- county travel patterns implied by the weighted, expanded "single day sample" of the 1990 household travel survey. The tables referred to in this text provide summaries of intra-county and inter-county home-based work trips and total trips. Detailed appendix tables provide county-to-county trip tables by trip purpose and travel mode. Home-based work trips by four travel modes (driver, in- vehicle, transit and total) for intra-county trips, production and attraction totals by county, are shown in Table 5.3.1. This table is useful in indicating the intra-county versus inter-county share of trips, by means of transportation, on a county-by-county basis. Regionally, 73.7 percent of all home-based work trips in the Bay Area are intra-county. This varies, by mode, from just 58.8 percent of all home-based work transit trips being intra-county to 76.1 percent of all home-based work vehicle driver trips. This means that home-based work transit trips are typically longer (i.e., more inter-county oriented) than home-based work vehicle driver trips. By county of production, Santa Clara County has the highest share of intra-county home-based work total trips, at 91.5 percent; the "bedroom" county of San Mateo County, has the lowest at 59.8 percent intra-county trips. The other two "bedroom" counties with low intra-county work trips are Marin (60.1 percent) and Contra Costa (60.6 percent). By county of attraction, 95.4 percent of the work trips attracted to Sonoma County are made by Sonoma County residents. At the other extreme, 55.8 percent of the home-based work trips attracted to jobs in San Francisco County are made by residents of San Francisco County. The low share of intra-county home-based work transit trips is notable in Contra Costa County (11.6 percent intra-county); Marin County (11.8 percent intra-county); and San Mateo County (17.0 percent intra-county). These three counties are exporting" most of their daily transit commuters to jobs in San Francisco, which explains the very low intra-county home-based work transit share. Trips for all trip purposes combined, by four travel modes (driver, in-vehicle, transit and total) for intra-county trips, production and attraction totals by county, are -132- shown in Table 5.3-2. Regionally, 86.7 percent of all trips made in the Bay Area are intra-county. This varies, by mode, from 73.1 percent of all transit trips being intra-county to 85.9 percent of all in-vehicle persons trips. San Mateo County has the lowest share of intra-county trips by all trip purposes at 76.5 percent. At the other extreme, 92.7 percent of all trips produced in Sonoma County are intra-county. By county of attraction, 76.1 percent of all trips attracted to San Francisco are intra-county; 96.3 percent of trips attracted to Sonoma County are intra-county. As with work trips, three counties show a very low intra- county transit share. Only 27.6 percent of transit trips produced in Contra Costa County are intra-county, 36.5 percent of transit trips produced in San Mateo County are intra-county; and 37.6 percent of transit trips produced in Marin County are intra-county. This is reflected in high number and share of transit trips destined to San Francisco. -133- Table 53.1 1990 Home-Based Work Trip Productions, Attractions,, and Intra- County Trips Click HERE for graphic. -134- Table 53.2 1990 Total Trip Productions, Attractions, and Intra-County Trips Click HERE for graphic. -135- 5.4 County-Level Vehicle Occupancy This last subsection of Working Paper #4 reports on private passenger vehicle occupancy rates by trip purpose by county of production and county of attraction. Vehicle occupancy rates are approximate calculations based on the number of vehicle driver trips plus the number of vehicle passenger trips, divided by the number of vehicle driver trips. It is important to note that these vehicle occupancy rates are only approximate estimates due to the nature of trip reporting in household travel surveys. There are many examples in the 1990 survey of "mixed purpose" trips, e.g., the vehicle driver's trip purpose is different than the vehicle passenger's trip purpose. For example, a trip with a parent driving a child to school, then driving home again, is classified as two home-based shop (other) vehicle driver trips. The child's trip, riding in the same vehicle, is classified as one home-based school passenger trip. This classification scheme results in very high vehicle occupancy rates (2.37 persons per vehicle) for home-based school trips given that the drivers of these trips are typically classified as either home-based shop (other) or home-based work trip purposes. Vehicle occupancy rates can also be based on the reported - vehicle occupancy in the trip diary. This reported vehicle occupancy data is important in distinguishing between drive alone and carpooling levels for in-vehicle persons, but typically provides very different vehicle occupancy estimates than the straightforward (vehicle driver + vehicle passenger / vehicle driver) calculation. The analysis of vehicle occupancy rates, comparing the trip diary vehicle occupancy data to the vehicle driver/vehicle passenger data is not included in this working paper. Given this ambiguity in the vehicle occupancy calculation, only vehicle occupancy rates for total trip purposes are analyzed here. The reader should interpret and use the trip purpose and county-level vehicle occupancy rates with caution. The average vehicle occupancy in the Bay Area is 1.24 persons per vehicle, for all trip purposes combined. This vehicle occupancy rate ranges from a low of 1.17 persons per vehicle for trips produced in Marin County to a high of 1.28 persons per vehicle for trips produced in Solano County. San Francisco County has the second highest vehicle occupancy rate at 1.26 persons per vehicle. Most of the counties have an average vehicle occupancy rate between 1.23 and 1.25 persons per vehicle. -136- Table 5.4 1990 Vehicle Occupancy by Trip Purpose Click HERE for graphic. Notes: Upper entry is vehicle occupancy rate by county of production. Lower entry is vehicle occupancy rate by county of attraction. -137- Appendix 1.0 BACKGROUND 1990 Household Travel Survey Questionnaire San Francisco Bay Regional Map -138- General and Detailed Trip Purpose and Travel Modes (1990 Survey codes shown in parentheses) General Trip Purposes 1. HBW Home-Based Work Home (1) <-> Work (2), Work-Related (3) 2. HBSH Home-Based Shop (Other) Home (1) <-> Personal Business (4), Medical/Dental (5), Grocery Shopping (9), Other Shopping (10), Child Care-Adult (12), Serve Adult Psgr. (13), Serve Child Psgr (14), Change Travel Mode (15), Other (16), Child Care-Child (17) 3. HBSR Home-Based Social/Rec Home (1) <-> Visiting (6), Eat Meal (7), Recreation (8) 4. HBSK Home-Based School Home (1) <-> School (11) 5. NHB Non-Home-Based Non-Home (2-17) <-> Non-Home (2-17) General Travel Modes 1. VD Vehicle Driver Auto Driver (1), Truck Driver (3), Van Driver (5), Motorcycle Driver (19) 2. VP Vehicle Passenger Auto Passenger (2), Truck Passenger (4), Van Passenger (6), Motorcycle Passenger (20) 3. TR Transit Passenger Public Bus Passenger (8), Cable Car (10), Streetcar (11), Shuttle Bus(12), Dial-a- Ride (13), BART (14), CalTrain (15), AMTRAK (16), Ferry Passenger (18) 4. SB School Bus Passenger School Bus Passenger (9) (only HBSK trips) 5. BI Bicycle Bicycle Rider 6. WK Walk Walk (23) 7. OM Other Means Taxi, Limo Passenger (7), Airplane (17), Moped (21), Other (24) -138a- Click HERE for graphic. -139- Click HERE for graphic. 1990 BAY AREA TRAVEL SURVEYS - TELEPHONE INTERVIEW FORM OCCUPANTS OF HOUSING UNIT INFORMATION QUESTION Now I would like to ask a few questions about each member of your household, 5 years old or older. These are necessary to better use the trip information you will be recording and providing the next time I call. [IF NECESSARY] This information will be kept and used In the strictest confidence for statistical and transportation planning purposes only. A. So I can keep track of the people of your household, please give nw your first name and the first name of each person 5 years old and older in your household, and the relationship of each person to you. [ALLOW RELATIONSHIPS ONLY, WITHOUT NAMES] [IF NECESSARY, ASK RESPONDENT:] What is your primary relationship In your household? [ASK ONLY IF NECESSARY] (Are you) B. (is NAME) male or female? ( M / F) (your) C. What is (NAME'S) age? [ASK ONLY FOR AGE 16 OR OVER] (Do you) D. (Does NAME) have a valid drivers license? (Y/N) (your) E. What term would you use to describe (NAME'S) ethnic background? 0 - White 2 - Hispanic, Mexican 5 - Chinese 1 - Black 3 - Hispanic, other 6 - Japanese 4 - Native American, 7 - Vietnamese Eskimo, Aleut 8 - Filipino 9 - Other Asian (your) F. What is (NAME'S) current employment status? [SELECT ONE OR TWO CATEGORIES] 1 - Employed full-time 4 - Student full-time 9 - Other 2 - Employed part-time 5 - Student part-time 3 - Retired 6 - Unemployed, looking for work [IF NOT EMPLOYED, SKIP NEXT 4 QUESTIONS AND GO TO QUESTION K] -141- 1990 BAY AREA TRAVEL SURVEYS - TELEPHONE INTERVIEW FORM OCCUPANTS OF HOUSING UNIT INFORMATION QUESTIONS (your) G. What is (NAME'S) occupation? 1 - Executive. Administrative and Managerial 2 - Professional Specialties (e.g., Engineer, Doctor, Teacher) 3 - Tech and Related Support ( eg., Health Tech, Lab Tech, Programmer, Legal Assistant) 4 - Sales 5 - Administrative Support Including Clerical 6 - Private Household (eg.. Child Care, Maid) 7 - Protective Service (e.g., Police, Fire, Guard) 8 - Service, except Private and Protective 9 - farming, Forestry or Fishing 10 - Precision Production, Craft or Repair 11 - Machine Operators, Assemblers or Inspectors 12 - Transportation on or Material Moving 13 - Handlers, Equipment Cleaners, Helpers or Laborers (are you) H. What kind of business (is NAME) in? 1 - Farming, Forestry, Fishing 6 - Wholesale Trade 2 - Miring 7 - Retail Trade 3 - Construction 8 - Finance, Insurance, Real Estate 4 - Manufacturing 9 - Services 5 - Transportation, Communications, 10 - Government, Public Admin,Public Utilities (you) L. What Is the address where (NAME) works? [ADDRESS AND CITY] [Please give a complete address if you can, or a well-known location, so we can locate it on a map for location coding.] (have you) J. How long (has NAME) been working at this location? [IF WORKED AT THIS LOCATION FOR LESS THAN 5 YEARS] (you) What city did (NAME) work in previously? [ASK QUESTION "K" ONCE, FOR EVERYONE IN HOUSEHOLD] K. Does anyone in your household have any physical, mental or other health condition which has lasted six months or more and which makes it difficult to use public transportation? [IF NO, SKIP TO RESPONDENT ADDRESS & APPOINTMENT FORM] (you) L. Compared to the average person, does this condition make it difficult for (NAME) to: [for each question, Y / N] 1. Walk or go up to three blocks? 2. Board a standard transit bus? 3. Ride seated in a standard transit bus? 4. Ride in a taxicab? 5. Are there other situations that make ft difficult for you to use public transportation? [IF YES] Please specify. -142- MTC METROPOLITAN TRANSPORTATION COMMISSION Dear Bay Area Resident: Recently you were called by a survey research interviewer working for the E. H. White Company under contract to the Metropolitan Transportation Commission. The Comission is conducting a survey throughout the Bay Area. the results of which will be used in determining the future transportation needs of this area. Thank you for agreeing to participate in this Bay Area Travel Survey. Enclosed are the materials described by the interviewer. Please read the attached sheet carefully as It explains how to record information about the trips made by members of your household. If you have any general questions about the survey, please call the E. H. White Travel Study Hotline at 1-800-675-5610. If you wish to verify that this is a valid KTC survey. please call Shirley Rodenborn, NTC Project Manager. at (415) 464-7700. Your participation in this survey is particularly important because the information gathered on people living in your household will be used to represent many people who live in the Bay Area. All the information you give will be treated in the strictest confidence and will be used for transportation planning purposes only. Thank you for your cooperation. Sincerely Lawerence D. Dahms Executive Director Enclosure LDD:SAR:my 0472t/2 -143- Joseph P. bort MetroCenter - 101 Eighth Street - Oakland, CA 94607-4700 - 415/464-7700 - FAX 415/464/7848 USING THE TRIP DIARIES TO RECORD YOUR TRIPS The Bay Area Travel Study requires information on how. when, where, and why people travel. The success of the survey and the usefulness of the results depend on how accurately you report all trips made during your assigned Three-day travel week by all household members age five and older. This includes visitors that are staying with you during the travel week. We have enclosed ___________ travel cards and ask that each household member fill out one of these cards recording all the trips he/she makes on your travel week. It is essential for our survey that you record your trips for each day of this travel week. Some suggestions on filling out your cards: 1. WHEN YOU 60 FROM ONE PLACE TO ANOTHER FOR ANY REASON. THIS IS A TRIP. For example. if on your way home from work you stop at a market and at the cleaners, record these as three separate trips. 2. Include all types of trips. For example. trips =de by walking or bicycle as well as by car, bus, etc. 3. Any time you change the method by which you travel, this Is a new trip. For example, if you drive to a friend's house and get in her/his car to go to work, shopping, etc., record these as two separate trips. 4. If members of your family or household make a group trip (for example, two or three of you ride at the same time in the same car or bus), record this trip on each person's trip card. 5. If you travel by bus, each time you transfer buses, record these as separate trips. 6. Please give as specific information as possible for the trip beginning and destination. For example, an exact address or the address range and street (e.g., 2700 block of Main St) and the city; the name of the BART station; the specific store (e.g., Racy's Union Square). We need this to assign geographic zone codes to each location. 7. Please write the purpose of each trip. Some examples are: work, home. food shopping, taking a child to child care, doctor, etc. As arranged in our previous conversation, we will be calling you on _____________________ to gather the information recorded on these trip cards. At that time we would prefer to interview each member of your household, but if some household members are not available or are young children. we can take the information recorded on their travel cards from another responsible adult. If you have questions about how to fill in your travel card-or any other question-please call our office at (415) 668-0076. Again. thanks for your cooperation. Sincerely, Harold Charns Survey Project Director 0484t/2 -144- Click HERE for graphic. Click HERE for graphic. Click HERE for graphic. 1990 BAY AREA TRAVEL SURVEYS - TELEPHONE INTERVIEW FORM TRIP INFORMATION - QUESTIONS (First) A. For the ( next ) trip, where did this trip begin? [PROMPT] Please give me the exact address, specific intersecting streets, or a well-known place, and the city. B. Where did this trip end? [ SAME PROMPT AS TRIP BEGINNING] C. On this trip, how did you travel? 1 = Auto Driver 13 = Dial-A-Ride Passenger 2 = Auto Passenger 14 = BART Passenger 3 = Truck Driver 15 = Southern Pacific Passenger 4 = Truck Passenger 16 = AMTRAK Passenger 5 = Van Driver 17 = Airplane Passenger 6 = Van Passenger 18 = Ferry Passenger 7 = Taxi or Limo Passenger 19 = Motorcycle Driver 8 = Public Bus Passenger [SPECIFY] 20 = Motorcycle 9 = School Bus Passenger 21 = Moped 10 = Cable Car Passenger 22 = Bicycle 11 = Streetcar Passenger 23 = Walk 12 = Shuttle Bus Passenger 24 = Other [SPECIFY] D. What was the purpose of this trip? 1 = Home 9 = Grocery Shopping 2 = Work 10 = Non-Grocery Shopping 3 = Work-Related 11 = Education 4 = Personal Business 12 = Child Care (Child / Provider 5 = Medical / Dental 13 = Serve Adult Passenger 6 = Visiting 14 = Other Serve Child Passenger 7 = Eat Meal 15 = Change Travel Mode 8 = Recreation 16 = Other E. What time did this trip start? [AS NEEDED] Was this in the morning or afternoon? F. What time did this trip end? (What time did you get to < DESTINATION > ?) [IF PUBLIC TRANSIT USED, SKIP TO QUESTION K.] G. How many people were in the vehicle? [IF MORE THAN ONE PERSON IN VEHICLE] Was this trip pre-arranged with the other people in the vehicle? -148- 1990 BAY AREA TRAVEL SURVEYS - TELEPHONE INTERVIEW FORM TRIP INFORMATION - QUESTIONS (Cont.) H. Which of your vehicles was used for this trip? [RECORD VEHICLE NUMBER FROM HOUSING UNIT QUESTION A - 6] L. What We of parking did you use? 1 = On-Street, free 6 = Service / Repair 2 = On-Street, Paid 7 = Resident parking 3 = Employee lot/ garage 8 = Cruising 4 = Lot/Garage,free 9 = Not parked 5 = Lot/ Garage, paid [IF PARKING IS PAID, NOT FREE] J. How much did you pay for parking? [IF NOT PAID AT TIME] How much do you pay, and how often? [RECORD AMOUNT IF ONE TIME, AMOUNT AND UNIT TIME IF REGULAR] K. It you crossed any bridges, which ones did you cross? 1 = San Francisco Bay 6 = Antic 2 = Golden Gate 7 = Benicia/Martinez 3 = San Mateo / Hayward 8 = Richmond/ San Rafael 4 = Dumbarton 9 = None crossed 5 = Carquinez [IF PUBLIC TRANSIT USED] [MAKE SURE BUS OPERATOR IS RECORDED IN QUESTION C] L. How was the fare paid for this trip? 1 = Cash How much was the fare? 2 = Pass What type of pass, and how much did it cost? 3 = Transfer Was it free or did you have to pay for it? 4 = Ticket /Token 5 = Other (SPECIFY] [AFTER ALL TRIPS ARE RECORDED FOR THE HOUSEHOLD] M. Have travel patterns changed for anyone in your household because of the earthquake? [IF YES] Could you tell me, briefly, how your travel has changed? [CONTINUE WITH END FORM] -149- 1990 BAY AREA TRAVEL SURVEYS--TELEPHONE INTERVIEW FOR SAMPLE NUMBER___________ ____________ ___ ___ ___ / ___ ___ ___ [RESPONDENT ADDRESS AND APPOINTMENT FORM] [RECORD AT END OF OCCUPANT INFORMATION] Thank you for your help in this portion of our survey. The last thing I need is your address to mail the trip diary cards. As I mentioned, we would like you and every person in your household 5 years old and over to record every trip or trip segment you make for (AN ENTIRE DAY)(SEVERAL DAYS). I will call you bad on ________ (DAY AND DATE) after you have completed the trip diary(IES) to record the trip information. [FOR MULTI-DAY TRIP DIARY HOUSEHOLDS] You will receivewhen the survey is completed. Name ______________________________________________________________ Address ___________________________________________________________ City _____________________ State __________________ Zip ___________ END FORM [COMPLETE AFTER TRAVEL INTERVIEW] Now, I love only three more questions to ask you to finish this interview. F. Would you be willing to repeat this interview, 1 = Yes including the trip diaries, in about a year or so? 2 = No [IF YES] So we can be sure to find you for the next survey, would you please tell me the name and address of a dose friend or relative not living with you who will always know how to find you? Name ____________________________________________________________ Address _________________________________________________________ City _____________________ State __________________ Zip _________ [IF NO] So we can better understand the reasons why some people won't be part of the survey next year, could you give nw a brief reason why you are not willing to repeat this interview next year? _________________________________________________________________ _________________________________________________________________ G. And finally, for statistical and travel forecasting purposes, we need to know your total household income before taxes. I will read several income ranges to you. Please stop me when we reach the right one. 1 = less than $5,000 10 = $45,000 to $49,999 2 = $5,00010 $9,999 11 = $50,000 to $59,999 3 = $10,000 to $14,999 12 = $60,000 to $74,999 4 = $15,000 to $19,999 13 = $75,000 to $99.999 5 = $20,000 to $24,999 14 = $100,000 to $124,999 6 = $25.000 to $29,999 15 = $125,000 and over 7 = $30,000 to $34,999 8 = $35,000 to $39,999 88 = Don't know 9 = $40,000 to $44,999 99 = Refused THANK YOU VERY MUCH FOR YOUR COOPERATION -150-
