Energy Information Administration
January 2009 Monthly Energy Review
Note: Information about data precision and revisions.
Posted: January 26, 2009
Next Update: Last week of February 2009
Table 9.11. Natural Gas Prices
| Year | Natural Gas, Wellhead Price (Nominal Dollars per Thousand Cubic Feet) | Natural Gas, City Gate Price (Nominal Dollars per Thousand Cubic Feet) | Natural Gas Price, Delivered to Residential Consumers (Nominal Dollars per Thousand Cubic Feet) | Percentage of Residential Sector Consumption for Which Price Data Are Available (Percent) | Natural Gas Price, Delivered to Commercial Consumers (Nominal Dollars per Thousand Cubic Feet) | Percentage of Commercial Sector Consumption for Which Price Data Are Available (Percent) | Natural Gas Price, Delivered to Industrial Consumers (Nominal Dollars per Thousand Cubic Feet) | Percentage of Industrial Sector Consumption for Which Price Data Are Available (Percent) | Natural Gas Price, Electric Power Sector (Nominal Dollars per Thousand Cubic Feet) | Percentage of Electric Power Sector Consumption for Which Price Data Are Available (Percent) |
| 1973 January | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 February | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 March | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 April | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 May | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 June | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 July | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 August | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 September | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 October | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 November | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 December | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1973 Average | 0.22 | Not Available | 1.29 | Not Available | 0.94 | Not Available | 0.5 | Not Available | 0.38 | 92.1 |
| 1974 January | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 February | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 March | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 April | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 May | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 June | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 July | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 August | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 September | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 October | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 November | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 December | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1974 Average | 0.3 | Not Available | 1.43 | Not Available | 1.07 | Not Available | 0.67 | Not Available | 0.51 | 92.7 |
| 1975 January | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 February | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 March | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 April | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 May | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 June | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 July | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 August | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 September | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 October | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 November | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 December | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1975 Average | 0.44 | Not Available | 1.71 | Not Available | 1.35 | Not Available | 0.96 | Not Available | 0.77 | 96.1 |
| 1976 January | 0.54 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 February | 0.54 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 March | 0.54 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 April | 0.55 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 May | 0.55 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 June | 0.58 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 July | 0.58 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 August | 0.6 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 September | 0.6 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 October | 0.62 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 November | 0.63 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 December | 0.64 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1976 Average | 0.58 | Not Available | 1.98 | Not Available | 1.64 | Not Available | 1.24 | Not Available | 1.06 | 96.2 |
| 1977 January | 0.67 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 February | 0.71 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 March | 0.75 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 April | 0.77 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 May | 0.77 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 June | 0.82 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 July | 0.83 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 August | 0.82 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 September | 0.83 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 October | 0.84 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 November | 0.83 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 December | 0.84 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1977 Average | 0.79 | Not Available | 2.35 | Not Available | 2.04 | Not Available | 1.5 | Not Available | 1.32 | 97.1 |
| 1978 January | 0.87 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 February | 0.88 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 March | 0.89 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 April | 0.88 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 May | 0.91 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 June | 0.91 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 July | 0.89 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 August | 0.91 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 September | 0.92 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 October | 0.92 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 November | 0.93 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 December | 0.96 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available |
| 1978 Average | 0.91 | Not Available | 2.56 | Not Available | 2.23 | Not Available | 1.7 | Not Available | 1.48 | 98 |
| 1979 January | 1.02 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.55 | Not Available |
| 1979 February | 1.05 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.65 | Not Available |
| 1979 March | 1.1 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.69 | Not Available |
| 1979 April | 1.11 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.7 | Not Available |
| 1979 May | 1.15 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.82 | Not Available |
| 1979 June | 1.17 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.84 | Not Available |
| 1979 July | 1.2 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.84 | Not Available |
| 1979 August | 1.24 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.87 | Not Available |
| 1979 September | 1.24 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.89 | Not Available |
| 1979 October | 1.28 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.96 | Not Available |
| 1979 November | 1.29 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.87 | Not Available |
| 1979 December | 1.31 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 1.9 | Not Available |
| 1979 Average | 1.18 | Not Available | 2.98 | Not Available | 2.73 | Not Available | 1.99 | Not Available | 1.81 | 96.1 |
| 1980 January | 1.37 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2 | Not Available |
| 1980 February | 1.42 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.1 | Not Available |
| 1980 March | 1.46 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.13 | Not Available |
| 1980 April | 1.51 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.09 | Not Available |
| 1980 May | 1.56 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.17 | Not Available |
| 1980 June | 1.57 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.15 | Not Available |
| 1980 July | 1.64 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.36 | Not Available |
| 1980 August | 1.64 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.45 | Not Available |
| 1980 September | 1.69 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.45 | Not Available |
| 1980 October | 1.71 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.52 | Not Available |
| 1980 November | 1.76 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.37 | Not Available |
| 1980 December | 1.74 | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | Not Available | 2.31 | Not Available |
| 1980 Average | 1.59 | Not Available | 3.68 | Not Available | 3.39 | Not Available | 2.56 | Not Available | 2.27 | 96.9 |
| 1981 January | 1.77 | Not Available | 3.94 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.51 | Not Available |
| 1981 February | 1.81 | Not Available | 3.99 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.67 | Not Available |
| 1981 March | 1.86 | Not Available | 4.06 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.71 | Not Available |
| 1981 April | 1.93 | Not Available | 4.11 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.81 | Not Available |
| 1981 May | 1.95 | Not Available | 4.29 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.92 | Not Available |
| 1981 June | 1.95 | Not Available | 4.3 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.95 | Not Available |
| 1981 July | 2.01 | Not Available | 4.32 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.97 | Not Available |
| 1981 August | 2.02 | Not Available | 4.3 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.99 | Not Available |
| 1981 September | 2.08 | Not Available | 4.47 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.95 | Not Available |
| 1981 October | 2.11 | Not Available | 4.5 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.07 | Not Available |
| 1981 November | 2.15 | Not Available | 4.53 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.07 | Not Available |
| 1981 December | 2.16 | Not Available | 4.55 | Not Available | Not Available | Not Available | Not Available | Not Available | 2.97 | Not Available |
| 1981 Average | 1.98 | Not Available | 4.29 | Not Available | 4 | Not Available | 3.14 | Not Available | 2.89 | 97.6 |
| 1982 January | 2.23 | Not Available | 4.65 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.07 | Not Available |
| 1982 February | 2.3 | Not Available | 4.69 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.18 | Not Available |
| 1982 March | 2.35 | Not Available | 4.78 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.25 | Not Available |
| 1982 April | 2.4 | Not Available | 4.86 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.32 | Not Available |
| 1982 May | 2.45 | Not Available | 5.17 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.42 | Not Available |
| 1982 June | 2.45 | Not Available | 5.2 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.57 | Not Available |
| 1982 July | 2.47 | Not Available | 5.23 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.69 | Not Available |
| 1982 August | 2.53 | Not Available | 5.23 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.67 | Not Available |
| 1982 September | 2.56 | Not Available | 5.41 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.67 | Not Available |
| 1982 October | 2.6 | Not Available | 5.66 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.68 | Not Available |
| 1982 November | 2.62 | Not Available | 5.68 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.61 | Not Available |
| 1982 December | 2.62 | Not Available | 5.74 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.64 | Not Available |
| 1982 Average | 2.46 | Not Available | 5.17 | Not Available | 4.82 | Not Available | 3.87 | 85.1 | 3.48 | 92.6 |
| 1983 January | 2.66 | Not Available | 5.86 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.57 | Not Available |
| 1983 February | 2.66 | Not Available | 5.87 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.41 | Not Available |
| 1983 March | 2.58 | Not Available | 6 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.45 | Not Available |
| 1983 April | 2.53 | Not Available | 6.06 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.35 | Not Available |
| 1983 May | 2.53 | Not Available | 6.22 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.55 | Not Available |
| 1983 June | 2.59 | Not Available | 6.2 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.58 | Not Available |
| 1983 July | 2.52 | Not Available | 6.21 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.72 | Not Available |
| 1983 August | 2.58 | Not Available | 6.18 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.75 | Not Available |
| 1983 September | 2.67 | Not Available | 6.19 | Not Available | Not Available | Not Available | Not Available | Not Available | 3.7 | Not Available |
| 1983 October | 2.58 | 3.97 | 6.7 | Not Available | 5.62 | Not Available | Not Available | Not Available | 3.62 | Not Available |
| 1983 November | 2.6 | 3.91 | 6.3 | Not Available | 5.67 | Not Available | Not Available | Not Available | 3.54 | Not Available |
| 1983 December | 2.61 | 3.88 | 5.94 | Not Available | 5.62 | Not Available | Not Available | Not Available | 3.49 | Not Available |
| 1983 Average | 2.59 | Not Available | 6.06 | Not Available | 5.59 | Not Available | 4.18 | 80.7 | 3.58 | 93.9 |
| 1984 January | 2.67 | 3.94 | 5.78 | Not Available | 5.49 | Not Available | 4.31 | Not Available | 3.49 | Not Available |
| 1984 February | 2.71 | 4.02 | 5.84 | Not Available | 5.54 | Not Available | 4.29 | Not Available | 3.55 | Not Available |
| 1984 March | 2.67 | 3.91 | 5.92 | Not Available | 5.57 | Not Available | 4.29 | Not Available | 3.47 | Not Available |
| 1984 April | 2.64 | 3.96 | 5.96 | Not Available | 5.52 | Not Available | 4.19 | Not Available | 3.53 | Not Available |
| 1984 May | 2.67 | 3.98 | 6.27 | Not Available | 5.6 | Not Available | 4.21 | Not Available | 3.72 | Not Available |
| 1984 June | 2.7 | 4.02 | 6.76 | Not Available | 5.67 | Not Available | 4.11 | Not Available | 3.73 | Not Available |
| 1984 July | 2.68 | 4.06 | 7.11 | Not Available | 5.6 | Not Available | 4.14 | Not Available | 3.86 | Not Available |
| 1984 August | 2.69 | 3.69 | 7.23 | Not Available | 5.47 | Not Available | 4.15 | Not Available | 3.8 | Not Available |
| 1984 September | 2.62 | 4.02 | 7.17 | Not Available | 5.53 | Not Available | 4.24 | Not Available | 3.8 | Not Available |
| 1984 October | 2.63 | 3.99 | 6.8 | Not Available | 5.54 | Not Available | 4.17 | Not Available | 3.72 | Not Available |
| 1984 November | 2.61 | 3.92 | 6.31 | Not Available | 5.56 | Not Available | 4.21 | Not Available | 3.72 | Not Available |
| 1984 December | 2.57 | 3.97 | 6.05 | Not Available | 5.6 | Not Available | 4.25 | Not Available | 3.69 | Not Available |
| 1984 Average | 2.66 | 3.95 | 6.12 | Not Available | 5.55 | Not Available | 4.22 | 74.7 | 3.7 | 94.4 |
| 1985 January | 2.64 | 3.89 | 5.97 | Not Available | 5.62 | Not Available | 4.22 | Not Available | 3.74 | Not Available |
| 1985 February | 2.71 | 3.94 | 5.86 | Not Available | 5.53 | Not Available | 4.26 | Not Available | 3.68 | Not Available |
| 1985 March | 2.62 | 3.97 | 5.99 | Not Available | 5.59 | Not Available | 4.16 | Not Available | 3.74 | Not Available |
| 1985 April | 2.64 | 3.91 | 6.11 | Not Available | 5.65 | Not Available | 4.01 | Not Available | 3.72 | Not Available |
| 1985 May | 2.53 | 3.89 | 6.59 | Not Available | 5.59 | Not Available | 3.88 | Not Available | 3.57 | Not Available |
| 1985 June | 2.58 | 3.86 | 6.96 | Not Available | 5.65 | Not Available | 3.78 | Not Available | 3.56 | Not Available |
| 1985 July | 2.51 | 3.69 | 7.07 | Not Available | 5.44 | Not Available | 3.92 | Not Available | 3.56 | Not Available |
| 1985 August | 2.47 | 3.7 | 7.21 | Not Available | 5.42 | Not Available | 3.94 | Not Available | 3.46 | Not Available |
| 1985 September | 2.42 | 3.68 | 7.06 | Not Available | 5.37 | Not Available | 3.84 | Not Available | 3.4 | Not Available |
| 1985 October | 2.37 | 3.59 | 6.5 | Not Available | 5.3 | Not Available | 3.78 | Not Available | 3.37 | Not Available |
| 1985 November | 2.36 | 3.46 | 6.13 | Not Available | 5.39 | Not Available | 3.84 | Not Available | 3.38 | Not Available |
| 1985 December | 2.28 | 3.45 | 5.7 | Not Available | 5.25 | Not Available | 3.7 | Not Available | 3.29 | Not Available |
| 1985 Average | 2.51 | 3.75 | 6.12 | Not Available | 5.5 | Not Available | 3.95 | 68.8 | 3.55 | 94 |
| 1986 January | 2.28 | 3.52 | 5.63 | Not Available | 5.25 | Not Available | 3.77 | Not Available | 3.2 | Not Available |
| 1986 February | 2.26 | 3.52 | 5.67 | Not Available | 5.28 | Not Available | 3.77 | Not Available | 2.85 | Not Available |
| 1986 March | 2.16 | 3.5 | 5.71 | Not Available | 5.25 | Not Available | 3.53 | Not Available | 2.6 | Not Available |
| 1986 April | 2.1 | 3.33 | 5.89 | Not Available | 5.23 | Not Available | 3.35 | Not Available | 2.44 | Not Available |
| 1986 May | 1.96 | 3.15 | 6.18 | Not Available | 5.19 | Not Available | 3.11 | Not Available | 2.41 | Not Available |
| 1986 June | 1.85 | 3.11 | 6.67 | Not Available | 5.09 | Not Available | 3.05 | Not Available | 2.27 | Not Available |
| 1986 July | 1.8 | 3.08 | 6.84 | Not Available | 5.02 | Not Available | 2.88 | Not Available | 2.23 | Not Available |
| 1986 August | 1.77 | 3.04 | 6.94 | Not Available | 4.9 | Not Available | 2.81 | Not Available | 2.22 | Not Available |
| 1986 September | 1.78 | 3.02 | 6.83 | Not Available | 4.93 | Not Available | 2.92 | Not Available | 2.22 | Not Available |
| 1986 October | 1.73 | 2.94 | 6.38 | Not Available | 4.88 | Not Available | 2.93 | Not Available | 2.19 | Not Available |
| 1986 November | 1.77 | 2.9 | 5.66 | Not Available | 4.74 | Not Available | 3.01 | Not Available | 2.23 | Not Available |
| 1986 December | 1.76 | 2.99 | 5.28 | Not Available | 4.73 | Not Available | 3 | Not Available | 2.35 | Not Available |
| 1986 Average | 1.94 | 3.22 | 5.83 | Not Available | 5.08 | Not Available | 3.23 | 59.8 | 2.43 | 91.7 |
| 1987 January | 1.74 | 2.98 | 5.3 | Not Available | 4.8 | Not Available | 3.11 | Not Available | 2.44 | Not Available |
| 1987 February | 1.73 | 3.03 | 5.34 | Not Available | 4.79 | Not Available | 3.3 | Not Available | 2.46 | Not Available |
| 1987 March | 1.73 | 2.91 | 5.36 | Not Available | 4.8 | Not Available | 3.16 | Not Available | 2.4 | Not Available |
| 1987 April | 1.69 | 2.86 | 5.46 | Not Available | 4.9 | Not Available | 2.99 | Not Available | 2.38 | Not Available |
| 1987 May | 1.65 | 2.81 | 5.98 | Not Available | 4.88 | Not Available | 2.81 | Not Available | 2.31 | Not Available |
| 1987 June | 1.65 | 2.84 | 6.55 | Not Available | 4.87 | Not Available | 2.76 | Not Available | 2.3 | Not Available |
| 1987 July | 1.66 | 2.92 | 6.78 | Not Available | 4.78 | Not Available | 2.81 | Not Available | 2.33 | Not Available |
| 1987 August | 1.63 | 2.89 | 6.84 | Not Available | 4.77 | Not Available | 2.74 | Not Available | 2.26 | Not Available |
| 1987 September | 1.56 | 2.83 | 6.64 | Not Available | 4.6 | Not Available | 2.75 | Not Available | 2.19 | Not Available |
| 1987 October | 1.57 | 2.69 | 5.85 | Not Available | 4.62 | Not Available | 2.77 | Not Available | 2.26 | Not Available |
| 1987 November | 1.64 | 2.76 | 5.42 | Not Available | 4.66 | Not Available | 2.89 | Not Available | 2.28 | Not Available |
| 1987 December | 1.7 | 2.84 | 5.13 | Not Available | 4.67 | Not Available | 3.01 | Not Available | 2.53 | Not Available |
| 1987 Average | 1.67 | 2.87 | 5.54 | Not Available | 4.77 | 93.1 | 2.94 | 47.4 | 2.32 | 91.6 |
| 1988 January | 1.96 | 2.91 | 5.08 | Not Available | 4.6 | 93.8 | 3.18 | 48.8 | 2.6 | Not Available |
| 1988 February | 1.84 | 2.95 | 5.09 | Not Available | 4.69 | 93.3 | 3.22 | 47.9 | 2.56 | Not Available |
| 1988 March | 1.7 | 2.87 | 5.18 | Not Available | 4.69 | 92.5 | 3.13 | 43.3 | 2.32 | Not Available |
| 1988 April | 1.59 | 2.79 | 5.35 | Not Available | 4.71 | 91.7 | 2.97 | 42.7 | 2.2 | Not Available |
| 1988 May | 1.52 | 2.75 | 5.87 | Not Available | 4.61 | 89.4 | 2.76 | 39.2 | 2.1 | Not Available |
| 1988 June | 1.53 | 2.87 | 6.5 | Not Available | 4.53 | 87.5 | 2.67 | 37.9 | 2.16 | Not Available |
| 1988 July | 1.56 | 2.87 | 6.74 | Not Available | 4.48 | 86.3 | 2.54 | 38.8 | 2.23 | Not Available |
| 1988 August | 1.62 | 2.92 | 6.92 | Not Available | 4.37 | 87.2 | 2.66 | 38.8 | 2.36 | Not Available |
| 1988 September | 1.53 | 3.05 | 6.79 | Not Available | 4.41 | 87.6 | 2.7 | 41.2 | 2.36 | Not Available |
| 1988 October | 1.68 | 2.92 | 5.95 | Not Available | 4.53 | 87.4 | 2.8 | 43.3 | 2.4 | Not Available |
| 1988 November | 1.76 | 2.98 | 5.56 | Not Available | 4.69 | 88.7 | 3 | 42.1 | 2.58 | Not Available |
| 1988 December | 1.89 | 3.08 | 5.39 | Not Available | 4.78 | 89.7 | 3.31 | 44.4 | 2.57 | Not Available |
| 1988 Average | 1.69 | 2.92 | 5.47 | Not Available | 4.63 | 90.7 | 2.95 | 42.6 | 2.33 | 89.6 |
| 1989 January | 1.99 | 3.17 | 5.41 | Not Available | 4.81 | 91 | 3.37 | 41.1 | 2.63 | Not Available |
| 1989 February | 1.81 | 3.1 | 5.38 | Not Available | 4.8 | 91.2 | 3.31 | 39.9 | 2.44 | Not Available |
| 1989 March | 1.69 | 2.89 | 5.45 | Not Available | 4.79 | 90.8 | 3.1 | 38.2 | 2.32 | Not Available |
| 1989 April | 1.56 | 2.83 | 5.54 | Not Available | 4.77 | 89.2 | 2.89 | 36.8 | 2.31 | Not Available |
| 1989 May | 1.61 | 2.94 | 5.93 | Not Available | 4.64 | 88.2 | 2.78 | 35.9 | 2.39 | Not Available |
| 1989 June | 1.65 | 2.98 | 6.58 | Not Available | 4.57 | 86.1 | 2.67 | 37 | 2.4 | Not Available |
| 1989 July | 1.65 | 3.08 | 6.92 | Not Available | 4.65 | 85.1 | 2.68 | 34 | 2.4 | Not Available |
| 1989 August | 1.61 | 3.04 | 7.07 | Not Available | 4.61 | 85.1 | 2.69 | 32.8 | 2.38 | Not Available |
| 1989 September | 1.55 | 2.99 | 6.8 | Not Available | 4.67 | 84.6 | 2.66 | 33.8 | 2.33 | Not Available |
| 1989 October | 1.58 | 2.84 | 6.06 | Not Available | 4.61 | 85.2 | 2.74 | 37.3 | 2.39 | Not Available |
| 1989 November | 1.66 | 2.98 | 5.56 | Not Available | 4.71 | 87.7 | 2.96 | 35 | 2.56 | Not Available |
| 1989 December | 1.92 | 3.1 | 5.3 | Not Available | 4.81 | 90.7 | 3.31 | 39.6 | 2.85 | Not Available |
| 1989 Average | 1.69 | 3.01 | 5.64 | 99.9 | 4.74 | 89.1 | 2.96 | 36.9 | 2.43 | 79.6 |
| 1990 January | 2.23 | 3.24 | 5.43 | Not Available | 4.97 | 90.8 | 3.53 | 43.2 | 3 | Not Available |
| 1990 February | 1.85 | 3.1 | 5.65 | Not Available | 5.05 | 88.8 | 3.41 | 38.9 | 2.76 | Not Available |
| 1990 March | 1.55 | 2.94 | 5.6 | Not Available | 4.92 | 88.3 | 3.08 | 36.8 | 2.37 | Not Available |
| 1990 April | 1.49 | 2.83 | 5.64 | Not Available | 4.82 | 86.9 | 2.85 | 33.8 | 2.28 | Not Available |
| 1990 May | 1.47 | 2.81 | 6 | Not Available | 4.63 | 85.5 | 2.68 | 32.2 | 2.18 | Not Available |
| 1990 June | 1.48 | 3 | 6.56 | Not Available | 4.56 | 83.8 | 2.58 | 31.3 | 2.16 | Not Available |
| 1990 July | 1.49 | 3.03 | 7.04 | Not Available | 4.45 | 81.8 | 2.5 | 33 | 2.21 | Not Available |
| 1990 August | 1.51 | 2.91 | 7.08 | Not Available | 4.55 | 81.7 | 2.52 | 33.4 | 2.23 | Not Available |
| 1990 September | 1.56 | 2.92 | 6.9 | Not Available | 4.55 | 80.3 | 2.6 | 32.6 | 2.21 | Not Available |
| 1990 October | 1.76 | 2.81 | 6.14 | Not Available | 4.66 | 81.2 | 2.69 | 32.8 | 2.45 | Not Available |
| 1990 November | 1.94 | 3.14 | 5.69 | Not Available | 4.81 | 84.7 | 3.02 | 35.7 | 2.79 | Not Available |
| 1990 December | 2.04 | 3.19 | 5.62 | Not Available | 4.92 | 87.9 | 3.25 | 37.8 | 2.89 | Not Available |
| 1990 Average | 1.71 | 3.03 | 5.8 | 99.2 | 4.83 | 86.6 | 2.93 | 35.2 | 2.38 | 76.8 |
| 1991 January | 1.96 | 3.08 | 5.54 | Not Available | 4.94 | 89.4 | 3.25 | 36.8 | 2.7 | Not Available |
| 1991 February | 1.62 | 2.94 | 5.56 | Not Available | 4.94 | 88.5 | 2.97 | 36.4 | 2.35 | Not Available |
| 1991 March | 1.49 | 2.78 | 5.6 | Not Available | 4.89 | 87.8 | 2.75 | 36.3 | 2.21 | Not Available |
| 1991 April | 1.5 | 2.74 | 5.9 | Not Available | 4.87 | 84 | 2.68 | 33.3 | 2.1 | Not Available |
| 1991 May | 1.48 | 2.76 | 6.28 | Not Available | 4.65 | 83.2 | 2.4 | 32.4 | 2.01 | Not Available |
| 1991 June | 1.43 | 2.86 | 6.97 | Not Available | 4.8 | 80 | 2.34 | 31.3 | 1.94 | Not Available |
| 1991 July | 1.34 | 2.74 | 7.23 | Not Available | 4.5 | 79.3 | 2.23 | 29.2 | 1.88 | Not Available |
| 1991 August | 1.43 | 2.78 | 7.36 | Not Available | 4.73 | 81.6 | 2.29 | 31.9 | 1.96 | Not Available |
| 1991 September | 1.59 | 2.91 | 6.92 | Not Available | 4.57 | 78.1 | 2.4 | 29.4 | 2.19 | Not Available |
| 1991 October | 1.82 | 2.92 | 6.2 | Not Available | 4.58 | 78.7 | 2.69 | 29.2 | 2.35 | Not Available |
| 1991 November | 1.89 | 2.92 | 5.51 | Not Available | 4.71 | 85.1 | 2.84 | 32.8 | 2.43 | Not Available |
| 1991 December | 2 | 3.05 | 5.51 | Not Available | 4.84 | 86.1 | 3.09 | 32.3 | 2.64 | Not Available |
| 1991 Average | 1.64 | 2.9 | 5.82 | 99.2 | 4.81 | 85.1 | 2.69 | 32.7 | 2.18 | 79.3 |
| 1992 January | 1.74 | 2.9 | 5.53 | Not Available | 4.85 | 87.1 | 3.04 | 31.8 | 2.49 | Not Available |
| 1992 February | 1.26 | 2.7 | 5.54 | Not Available | 5.03 | 85.2 | 2.78 | 31.4 | 2.03 | Not Available |
| 1992 March | 1.35 | 2.61 | 5.5 | Not Available | 4.77 | 84.7 | 2.58 | 29.9 | 1.99 | Not Available |
| 1992 April | 1.42 | 2.74 | 5.62 | Not Available | 4.77 | 84 | 2.54 | 31.3 | 2.07 | Not Available |
| 1992 May | 1.51 | 2.9 | 6.15 | Not Available | 4.59 | 79.3 | 2.44 | 29.8 | 2.11 | Not Available |
| 1992 June | 1.62 | 3 | 6.84 | Not Available | 4.72 | 79.4 | 2.53 | 28 | 2.18 | Not Available |
| 1992 July | 1.55 | 3.01 | 7.27 | Not Available | 4.64 | 76 | 2.54 | 27.4 | 2.13 | Not Available |
| 1992 August | 1.84 | 3.18 | 7.45 | Not Available | 4.73 | 76.1 | 2.71 | 28.6 | 2.42 | Not Available |
| 1992 September | 1.92 | 3.23 | 7.15 | Not Available | 4.69 | 78 | 2.82 | 29.3 | 2.51 | Not Available |
| 1992 October | 2.38 | 3.5 | 6.52 | Not Available | 4.9 | 80.9 | 3.21 | 31.4 | 3.04 | Not Available |
| 1992 November | 2.13 | 3.33 | 6.02 | Not Available | 5.12 | 83.1 | 3.26 | 30.8 | 2.87 | Not Available |
| 1992 December | 2.07 | 3.17 | 5.74 | Not Available | 5.11 | 85.6 | 3.38 | 32.5 | 2.81 | Not Available |
| 1992 Average | 1.74 | 3.01 | 5.89 | 99.1 | 4.88 | 83.2 | 2.84 | 30.3 | 2.36 | 76.5 |
| 1993 January | 2.03 | 3.11 | 5.73 | Not Available | 5.23 | 86.6 | 3.15 | 32.6 | 2.7 | Not Available |
| 1993 February | 1.93 | 2.94 | 5.73 | Not Available | 5.14 | 86.3 | 3.02 | 32.9 | 2.54 | Not Available |
| 1993 March | 2 | 3.06 | 5.67 | Not Available | 5.1 | 86.4 | 2.98 | 32 | 2.61 | Not Available |
| 1993 April | 2.06 | 3.24 | 6.02 | Not Available | 5.19 | 84.9 | 3.04 | 30.7 | 2.75 | Not Available |
| 1993 May | 2.18 | 3.58 | 6.78 | Not Available | 5.31 | 82.2 | 3.14 | 29.6 | 2.9 | Not Available |
| 1993 June | 1.98 | 3.44 | 7.37 | Not Available | 5.4 | 79 | 2.86 | 27.4 | 2.48 | Not Available |
| 1993 July | 1.99 | 3.34 | 7.86 | Not Available | 5.15 | 79.2 | 2.62 | 28.3 | 2.45 | Not Available |
| 1993 August | 2.04 | 3.35 | 8.13 | Not Available | 5.34 | 78 | 2.76 | 27.6 | 2.6 | Not Available |
| 1993 September | 2.09 | 3.54 | 7.75 | Not Available | 5.35 | 78.3 | 2.95 | 27 | 2.69 | Not Available |
| 1993 October | 2.02 | 3.15 | 6.79 | Not Available | 5.18 | 79.9 | 2.77 | 28.1 | 2.45 | Not Available |
| 1993 November | 2.03 | 3.15 | 6.17 | Not Available | 5.21 | 83 | 3.02 | 29.8 | 2.59 | Not Available |
| 1993 December | 2.15 | 3.27 | 6.07 | Not Available | 5.33 | 85.1 | 3.28 | 29.5 | 2.76 | Not Available |
| 1993 Average | 2.04 | 3.21 | 6.16 | 99.1 | 5.22 | 83.9 | 3.07 | 29.7 | 2.61 | 74.1 |
| 1994 January | 1.93 | 3.04 | 5.93 | Not Available | 5.5 | 83.7 | 3.47 | 27.9 | 2.67 | Not Available |
| 1994 February | 1.88 | 3.26 | 6.04 | Not Available | 5.58 | 83.9 | 3.43 | 30 | 2.8 | Not Available |
| 1994 March | 1.93 | 3.33 | 6.3 | Not Available | 5.67 | 82.8 | 3.47 | 28.6 | 2.67 | Not Available |
| 1994 April | 1.91 | 3.15 | 6.6 | Not Available | 5.6 | 78.6 | 3.01 | 26.7 | 2.44 | Not Available |
| 1994 May | 2 | 3.17 | 6.84 | Not Available | 5.47 | 74.5 | 2.92 | 25.6 | 2.46 | Not Available |
| 1994 June | 1.8 | 3.17 | 7.66 | Not Available | 5.37 | 70.5 | 2.69 | 23.3 | 2.25 | Not Available |
| 1994 July | 1.81 | 3.12 | 8.1 | Not Available | 5.25 | 68.7 | 2.77 | 23.9 | 2.27 | Not Available |
| 1994 August | 1.83 | 3.15 | 8.22 | Not Available | 5.31 | 72.6 | 2.67 | 23.5 | 2.16 | Not Available |
| 1994 September | 1.78 | 2.92 | 7.84 | Not Available | 5.36 | 72.2 | 2.55 | 22 | 2 | Not Available |
| 1994 October | 1.7 | 2.8 | 6.86 | Not Available | 5.11 | 74.3 | 2.49 | 23.7 | 1.95 | Not Available |
| 1994 November | 1.75 | 2.84 | 6.27 | Not Available | 5.19 | 77.8 | 2.86 | 24.1 | 2.1 | Not Available |
| 1994 December | 1.88 | 2.86 | 6.06 | Not Available | 5.24 | 82.1 | 2.99 | 25.8 | 2.17 | Not Available |
| 1994 Average | 1.85 | 3.07 | 6.41 | 99.1 | 5.44 | 79.3 | 3.05 | 25.5 | 2.28 | 73.4 |
| 1995 January | 1.62 | 2.79 | 5.85 | Not Available | 5.23 | 81.6 | 2.95 | 27.3 | 2.13 | Not Available |
| 1995 February | 1.48 | 2.71 | 5.76 | Not Available | 5.14 | 81.7 | 2.85 | 27.4 | 2 | Not Available |
| 1995 March | 1.47 | 2.74 | 5.84 | Not Available | 5.12 | 81.2 | 2.74 | 26.5 | 1.92 | Not Available |
| 1995 April | 1.52 | 2.72 | 6.06 | Not Available | 5.08 | 77.2 | 2.57 | 25.4 | 1.97 | Not Available |
| 1995 May | 1.55 | 2.8 | 6.54 | Not Available | 5.04 | 71.8 | 2.54 | 23.6 | 2.06 | Not Available |
| 1995 June | 1.58 | 2.89 | 7.49 | Not Available | 5.16 | 71.4 | 2.44 | 24.5 | 2.06 | Not Available |
| 1995 July | 1.43 | 2.89 | 7.82 | Not Available | 5.03 | 67.3 | 2.34 | 22.2 | 1.9 | Not Available |
| 1995 August | 1.43 | 2.87 | 8.13 | Not Available | 4.99 | 66.6 | 2.26 | 21.8 | 1.84 | Not Available |
| 1995 September | 1.52 | 2.89 | 7.73 | Not Available | 4.98 | 67.9 | 2.42 | 22 | 1.95 | Not Available |
| 1995 October | 1.54 | 2.83 | 6.62 | Not Available | 4.82 | 69.7 | 2.44 | 22.5 | 2.09 | Not Available |
| 1995 November | 1.61 | 2.67 | 5.61 | Not Available | 4.77 | 75.6 | 2.68 | 24.7 | 2.22 | Not Available |
| 1995 December | 1.84 | 2.83 | 5.54 | Not Available | 5 | 79.2 | 3.07 | 25 | 2.58 | Not Available |
| 1995 Average | 1.55 | 2.78 | 6.06 | 99 | 5.05 | 76.7 | 2.71 | 24.5 | 2.02 | 71.4 |
| 1996 January | 2.05 | 3.14 | 5.64 | Not Available | 5.29 | 83.2 | 3.61 | 22 | 2.87 | Not Available |
| 1996 February | 1.89 | 3.16 | 5.82 | Not Available | 5.25 | 83.3 | 3.61 | 22.7 | 3.07 | Not Available |
| 1996 March | 1.95 | 3.17 | 5.93 | Not Available | 5.36 | 81.8 | 3.52 | 22.3 | 2.73 | Not Available |
| 1996 April | 2.08 | 3.22 | 6.27 | Not Available | 5.34 | 79.5 | 3.42 | 20.5 | 2.68 | Not Available |
| 1996 May | 2.01 | 3.18 | 6.84 | Not Available | 5.4 | 74.6 | 3.14 | 18.7 | 2.52 | Not Available |
| 1996 June | 2.08 | 3.41 | 7.83 | Not Available | 5.43 | 70 | 3.13 | 16.7 | 2.59 | Not Available |
| 1996 July | 2.25 | 3.49 | 8.64 | Not Available | 5.46 | 67.8 | 3.17 | 18.6 | 2.69 | Not Available |
| 1996 August | 2.1 | 3.46 | 8.73 | Not Available | 5.56 | 66.3 | 3.05 | 17.4 | 2.57 | Not Available |
| 1996 September | 1.85 | 3.05 | 7.99 | Not Available | 5.46 | 67.1 | 2.77 | 16.9 | 2.24 | Not Available |
| 1996 October | 1.94 | 2.94 | 7.05 | Not Available | 5.33 | 69.1 | 2.89 | 17.2 | 2.37 | Not Available |
| 1996 November | 2.5 | 3.46 | 6.37 | Not Available | 5.4 | 75.7 | 3.57 | 18.5 | 3.04 | Not Available |
| 1996 December | 3.26 | 4.18 | 6.47 | Not Available | 5.78 | 78.1 | 4.2 | 20 | 3.98 | Not Available |
| 1996 Average | 2.17 | 3.34 | 6.34 | 99 | 5.4 | 77.6 | 3.42 | 19.4 | 2.69 | 68.4 |
| 1997 January | 3.4 | 4.28 | 6.74 | Not Available | 6.19 | 78.7 | 4.6 | 17.5 | 4.06 | Not Available |
| 1997 February | 2.49 | 3.76 | 6.79 | Not Available | 6.14 | 78.3 | 4.18 | 17.8 | 2.97 | Not Available |
| 1997 March | 1.79 | 3.07 | 6.52 | Not Available | 5.73 | 73.9 | 3.34 | 17.9 | 2.29 | Not Available |
| 1997 April | 1.81 | 2.92 | 6.53 | Not Available | 5.46 | 71.8 | 3.1 | 18 | 2.3 | Not Available |
| 1997 May | 2 | 3.11 | 6.83 | Not Available | 5.39 | 65.5 | 3.04 | 17.6 | 2.41 | Not Available |
| 1997 June | 2.08 | 3.41 | 8.3 | Not Available | 5.64 | 61.6 | 3.19 | 17.5 | 2.52 | Not Available |
| 1997 July | 2 | 3.44 | 8.78 | Not Available | 5.35 | 59.4 | 3.11 | 17.6 | 2.44 | Not Available |
| 1997 August | 2.08 | 3.34 | 8.99 | Not Available | 5.43 | 57.9 | 3 | 17.7 | 2.53 | Not Available |
| 1997 September | 2.33 | 3.5 | 8.84 | Not Available | 5.58 | 59.4 | 3.32 | 17.4 | 2.96 | Not Available |
| 1997 October | 2.68 | 3.86 | 7.69 | Not Available | 5.74 | 62.8 | 3.69 | 17.7 | 3.24 | Not Available |
| 1997 November | 2.92 | 4.76 | 6.86 | Not Available | 5.86 | 70.3 | 4.02 | 17.6 | 3.41 | Not Available |
| 1997 December | 2.28 | 3.42 | 6.54 | Not Available | 5.72 | 72.9 | 3.74 | 17.7 | 2.77 | Not Available |
| 1997 Average | 2.32 | 3.66 | 6.94 | 98.8 | 5.8 | 70.8 | 3.59 | 18.1 | 2.78 | 68 |
| 1998 January | 1.96 | 3.08 | 6.41 | Not Available | 5.65 | 73.2 | 3.67 | 16.8 | 2.64 | Not Available |
| 1998 February | 1.96 | 3.08 | 6.41 | Not Available | 5.59 | 72.9 | 3.58 | 16.7 | 2.51 | Not Available |
| 1998 March | 2.06 | 3.06 | 6.29 | Not Available | 5.4 | 73.6 | 3.4 | 17.3 | 2.53 | Not Available |
| 1998 April | 2.16 | 3.23 | 6.81 | Not Available | 5.64 | 67.7 | 3.28 | 15.8 | 2.59 | Not Available |
| 1998 May | 2.04 | 3.12 | 7.7 | Not Available | 5.73 | 62.6 | 3.14 | 14.9 | 2.47 | Not Available |
| 1998 June | 1.91 | 2.98 | 8.51 | Not Available | 5.51 | 62.9 | 2.97 | 15.1 | 2.4 | Not Available |
| 1998 July | 2.09 | 3.31 | 8.53 | Not Available | 5.64 | 56 | 3.04 | 13.1 | 2.5 | Not Available |
| 1998 August | 1.82 | 3.01 | 9.25 | Not Available | 5.46 | 53.3 | 2.75 | 13.8 | 2.21 | Not Available |
| 1998 September | 1.7 | 2.78 | 8.96 | Not Available | 5.49 | 57 | 2.65 | 14.2 | 2.15 | Not Available |
| 1998 October | 1.86 | 2.99 | 7.6 | Not Available | 5.31 | 59.2 | 2.75 | 14.8 | 2.22 | Not Available |
| 1998 November | 1.94 | 2.99 | 6.58 | Not Available | 5.22 | 64.5 | 2.95 | 15.7 | 2.37 | Not Available |
| 1998 December | 1.95 | 3.1 | 6.34 | Not Available | 5.23 | 68.3 | 2.92 | 17.2 | 2.22 | Not Available |
| 1998 Average | 1.96 | 3.07 | 6.82 | 97.7 | 5.48 | 67 | 3.14 | 16.1 | 2.4 | 63.7 |
| 1999 January | 1.85 | 2.85 | 6 | Not Available | 5.19 | 73.1 | 3.29 | 16.9 | 2.32 | Not Available |
| 1999 February | 1.77 | 2.92 | 6.29 | Not Available | 5.28 | 69.7 | 2.92 | 16.8 | 2.26 | Not Available |
| 1999 March | 1.7 | 2.77 | 6.06 | Not Available | 4.97 | 69.2 | 2.96 | 17.4 | 2.15 | Not Available |
| 1999 April | 1.9 | 2.88 | 6.44 | Not Available | 5.31 | 65.3 | 3 | 16.6 | 2.29 | Not Available |
| 1999 May | 2.17 | 3.25 | 7.3 | Not Available | 5.34 | 61 | 2.86 | 16 | 2.57 | Not Available |
| 1999 June | 2.14 | 3.12 | 8.2 | Not Available | 5.29 | 61 | 2.82 | 15.8 | 2.53 | Not Available |
| 1999 July | 2.2 | 3.11 | 8.83 | Not Available | 5.43 | 58.2 | 2.86 | 15.7 | 2.58 | Not Available |
| 1999 August | 2.51 | 3.39 | 9.14 | Not Available | 5.45 | 56.5 | 2.98 | 18.9 | 2.86 | Not Available |
| 1999 September | 2.62 | 3.59 | 8.63 | Not Available | 5.55 | 60 | 3.4 | 17.6 | 2.98 | Not Available |
| 1999 October | 2.52 | 3.21 | 7.56 | Not Available | 5.46 | 61.6 | 3.2 | 17.5 | 2.83 | Not Available |
| 1999 November | 2.68 | 3.71 | 7.15 | Not Available | 5.72 | 63 | 3.51 | 17.7 | 3.01 | Not Available |
| 1999 December | 2.24 | 3.19 | 6.51 | Not Available | 5.57 | 67.9 | 3.16 | 21.2 | 2.68 | Not Available |
| 1999 Average | 2.19 | 3.1 | 6.69 | 95.2 | 5.33 | 66.1 | 3.12 | 18.8 | 2.62 | 58.3 |
| 2000 January | 2.6 | 3.27 | 6.37 | Not Available | 5.77 | 67.2 | 3.41 | 18.7 | 2.74 | Not Available |
| 2000 February | 2.73 | 3.48 | 6.54 | Not Available | 5.95 | 68.2 | 3.68 | 19.4 | 2.96 | Not Available |
| 2000 March | 2.66 | 3.54 | 6.91 | Not Available | 5.78 | 63.6 | 3.54 | 18.2 | 3 | Not Available |
| 2000 April | 2.86 | 3.72 | 7.19 | Not Available | 6.03 | 62.3 | 3.59 | 18 | 3.23 | Not Available |
| 2000 May | 3.04 | 4.15 | 8.26 | Not Available | 5.97 | 60.9 | 3.67 | 17 | 3.63 | Not Available |
| 2000 June | 3.77 | 5.19 | 9.5 | Not Available | 6.49 | 58 | 4.24 | 18.1 | 4.45 | Not Available |
| 2000 July | 3.84 | 5.2 | 10.32 | Not Available | 6.55 | 57 | 4.55 | 17.6 | 4.35 | Not Available |
| 2000 August | 3.73 | 4.63 | 10.37 | Not Available | 6.08 | 59.2 | 4.33 | 17.1 | 4.27 | Not Available |
| 2000 September | 4.26 | 5.21 | 10.1 | Not Available | 6.92 | 57.5 | 4.88 | 16.5 | 4.85 | Not Available |
| 2000 October | 4.58 | 5.66 | 9.44 | Not Available | 7.48 | 59.8 | 5.45 | 16.6 | 5.17 | Not Available |
| 2000 November | 4.4 | 5.2 | 8.58 | Not Available | 7.57 | 63.9 | 5.39 | 19.8 | 5.37 | Not Available |
| 2000 December | 5.77 | 6.64 | 8.56 | Not Available | 8.2 | 68.3 | 6.67 | 20.4 | 8.23 | Not Available |
| 2000 Average | 3.68 | 4.62 | 7.76 | 92.6 | 6.59 | 63.9 | 4.45 | 19.8 | 4.38 | 50.5 |
| 2001 January | 6.82 | 8.91 | 10.12 | Not Available | 9.5 | 72.9 | 8.84 | 23.5 | 9.55 | 0 |
| 2001 February | 5.08 | 7.08 | 10.26 | Not Available | 9.8 | 71.8 | 7.21 | 23.2 | 7.18 | 0 |
| 2001 March | 4.37 | 6.1 | 9.85 | Not Available | 9.14 | 69.2 | 6.3 | 22 | 5.91 | 0 |
| 2001 April | 4.52 | 6.3 | 10.16 | Not Available | 9.01 | 66.5 | 6.08 | 21 | 5.82 | 0 |
| 2001 May | 4.36 | 5.77 | 11.14 | Not Available | 9.19 | 61 | 5.46 | 19.5 | 5.29 | 0 |
| 2001 June | 3.79 | 5.38 | 11.58 | Not Available | 8.5 | 59.6 | 4.75 | 19.2 | 4.37 | 0 |
| 2001 July | 3.35 | 4.03 | 11.22 | Not Available | 7.9 | 54.6 | 4.1 | 20.2 | 3.85 | 0 |
| 2001 August | 3.33 | 4.32 | 10.89 | Not Available | 7.61 | 53.9 | 3.99 | 19.6 | 3.65 | 0 |
| 2001 September | 2.93 | 3.66 | 10.17 | Not Available | 6.96 | 54 | 3.5 | 19.8 | 3.03 | 0 |
| 2001 October | 2.78 | 3.37 | 8.24 | Not Available | 6.39 | 60.1 | 3.18 | 20.3 | 2.78 | 0 |
| 2001 November | 3.41 | 4.02 | 7.98 | Not Available | 6.79 | 65 | 3.88 | 20.2 | 3.33 | 0 |
| 2001 December | 3.42 | 3.9 | 7.3 | Not Available | 6.35 | 68.1 | 3.69 | 20.7 | 3.15 | 0 |
| 2001 Average | 4 | 5.72 | 9.63 | 92.4 | 8.43 | 66 | 5.24 | 20.8 | 4.61 | 40.2 |
| 2002 January | 2.5 | 3.79 | 7.38 | Not Available | 6.51 | 79.8 | 4.05 | 20.3 | 3.1 | 79.7 |
| 2002 February | 2.19 | 3.76 | 7.23 | Not Available | 6.4 | 80.7 | 3.7 | 20.6 | 2.86 | 86.2 |
| 2002 March | 2.4 | 3.84 | 7.1 | Not Available | 6.28 | 81.5 | 3.78 | 20.2 | 3.37 | 84.7 |
| 2002 April | 2.94 | 4.21 | 7.66 | Not Available | 6.56 | 76.8 | 3.64 | 26.3 | 3.8 | 84 |
| 2002 May | 2.94 | 4.07 | 8.54 | Not Available | 6.68 | 73 | 4.07 | 24 | 3.78 | 84.4 |
| 2002 June | 2.96 | 4.15 | 9.58 | Not Available | 6.8 | 73.2 | 3.86 | 25.6 | 3.61 | 82.6 |
| 2002 July | 2.92 | 3.95 | 10.31 | Not Available | 6.62 | 71.2 | 3.8 | 24 | 3.49 | 80.3 |
| 2002 August | 2.76 | 3.67 | 10.44 | Not Available | 6.45 | 71.6 | 3.62 | 22.6 | 3.42 | 82.8 |
| 2002 September | 2.97 | 3.99 | 10.23 | Not Available | 6.54 | 69.5 | 3.89 | 22.5 | 3.71 | 84.2 |
| 2002 October | 3.24 | 4.32 | 8.61 | Not Available | 6.64 | 73.2 | 4.18 | 21.7 | 4.19 | 85.5 |
| 2002 November | 3.59 | 4.65 | 7.99 | Not Available | 6.89 | 78.7 | 4.72 | 21.9 | 4.35 | 86.7 |
| 2002 December | 3.96 | 4.74 | 7.87 | Not Available | 7.16 | 79.6 | 4.92 | 23.2 | 4.72 | 91.8 |
| 2002 Average | 2.95 | 4.12 | 7.89 | 97.9 | 6.63 | 77.4 | 4.02 | 22.7 | 3.68 | 83.9 |
| 2003 January | 4.43 | 5.28 | 8.18 | Not Available | 7.48 | 79.9 | 5.65 | 21.4 | 5.33 | 89.4 |
| 2003 February | 5.05 | 5.83 | 8.58 | Not Available | 7.98 | 80.7 | 6.4 | 22.1 | 6.47 | 89.6 |
| 2003 March | 6.96 | 7.63 | 9.77 | Not Available | 9.2 | 80.8 | 8.27 | 21.3 | 7.05 | 90.8 |
| 2003 April | 4.47 | 5.6 | 10.18 | Not Available | 8.97 | 77.9 | 5.96 | 20.9 | 5.38 | 90.7 |
| 2003 May | 4.77 | 5.69 | 10.79 | Not Available | 8.71 | 74.2 | 5.78 | 20.3 | 5.7 | 94.2 |
| 2003 June | 5.41 | 6.4 | 12.08 | Not Available | 9 | 74.7 | 6.59 | 19.1 | 6.08 | 91.8 |
| 2003 July | 5.08 | 5.83 | 12.75 | Not Available | 8.73 | 72.4 | 5.69 | 24.7 | 5.45 | 92.4 |
| 2003 August | 4.46 | 5.48 | 12.84 | Not Available | 8.4 | 74.5 | 5.28 | 22.9 | 5.23 | 90.2 |
| 2003 September | 4.59 | 5.58 | 12.31 | Not Available | 8.41 | 73.5 | 5.32 | 22.9 | 5.12 | 91.3 |
| 2003 October | 4.32 | 5.33 | 10.64 | Not Available | 8.28 | 74.6 | 4.93 | 23.3 | 4.98 | 90.9 |
| 2003 November | 4.26 | 5.54 | 9.77 | Not Available | 8.36 | 78 | 5.19 | 22.7 | 4.85 | 91.3 |
| 2003 December | 4.76 | 5.89 | 9.51 | Not Available | 8.62 | 80.5 | 5.9 | 23.5 | 5.69 | 91.5 |
| 2003 Average | 4.88 | 5.85 | 9.63 | 97.5 | 8.4 | 78.2 | 5.89 | 22.1 | 5.57 | 91.2 |
| 2004 January | 5.21 | 6.41 | 9.71 | Not Available | 9.06 | 81.6 | 6.72 | 23.2 | 6.37 | 90.1 |
| 2004 February | 5.02 | 6.35 | 9.85 | Not Available | 9.1 | 81.7 | 6.52 | 23.6 | 5.76 | 88.7 |
| 2004 March | 5.12 | 6.23 | 10.03 | Not Available | 9.05 | 79.2 | 5.97 | 22.9 | 5.5 | 91.4 |
| 2004 April | 5.03 | 6.31 | 10.54 | Not Available | 9.02 | 77.7 | 6.06 | 23.4 | 5.74 | 92.5 |
| 2004 May | 5.4 | 6.48 | 11.63 | Not Available | 9.23 | 73.8 | 6.34 | 23.5 | 6.3 | 89.5 |
| 2004 June | 5.82 | 6.94 | 13.08 | Not Available | 9.71 | 72.2 | 6.82 | 25 | 6.52 | 89.4 |
| 2004 July | 5.62 | 6.68 | 13.54 | Not Available | 9.65 | 71.7 | 6.41 | 24.9 | 6.24 | 90.3 |
| 2004 August | 5.52 | 6.51 | 13.74 | Not Available | 9.66 | 71 | 6.36 | 24.1 | 5.97 | 89.8 |
| 2004 September | 5.06 | 6.06 | 13.31 | Not Available | 9.26 | 71.4 | 5.68 | 22.9 | 5.39 | 89.2 |
| 2004 October | 5.43 | 6.3 | 11.69 | Not Available | 9.17 | 73.3 | 6.03 | 22.6 | 6.05 | 90.4 |
| 2004 November | 6.21 | 7.5 | 11.44 | Not Available | 10.21 | 78 | 7.64 | 23.5 | 6.71 | 87.9 |
| 2004 December | 6.01 | 7.49 | 11.09 | Not Available | 10.42 | 80.3 | 7.54 | 24.5 | 6.88 | 88 |
| 2004 Average | 5.46 | 6.65 | 10.75 | 97.7 | 9.43 | 78 | 6.53 | 23.7 | 6.11 | 89.8 |
| 2005 January | 5.8 | 7.05 | 10.9 | Not Available | 10.02 | 84.8 | 7.06 | 24.9 | 6.72 | 93 |
| 2005 February | 5.73 | 7.09 | 10.87 | Not Available | 9.83 | 85 | 7.15 | 24.3 | 6.42 | 93.4 |
| 2005 March | 5.95 | 7.24 | 10.84 | Not Available | 9.91 | 84.4 | 7.12 | 24.6 | 6.84 | 92.8 |
| 2005 April | 6.57 | 7.79 | 11.88 | Not Available | 10.25 | 82.6 | 7.71 | 23.9 | 7.27 | 92.8 |
| 2005 May | 6.25 | 7.51 | 12.74 | Not Available | 10.35 | 79.4 | 7.19 | 24.2 | 6.83 | 93.5 |
| 2005 June | 6.09 | 7.3 | 13.79 | Not Available | 10.22 | 78.2 | 6.91 | 23.7 | 7.08 | 90.8 |
| 2005 July | 6.71 | 7.68 | 14.86 | Not Available | 10.58 | 75.6 | 7.4 | 24.5 | 7.57 | 89.7 |
| 2005 August | 6.48 | 8.2 | 15.51 | Not Available | 11.01 | 76.2 | 7.98 | 24.6 | 8.67 | 89.1 |
| 2005 September | 8.95 | 10.26 | 16.56 | Not Available | 12.59 | 74.8 | 10.18 | 23.2 | 10.99 | 90 |
| 2005 October | 10.33 | 12.16 | 16.44 | Not Available | 14.29 | 78.9 | 12.06 | 23.2 | 11.84 | 92.1 |
| 2005 November | 9.89 | 11.57 | 15.64 | Not Available | 14.76 | 81.3 | 12.11 | 23.5 | 9.87 | 93.7 |
| 2005 December | 9.08 | 10.77 | 14.6 | Not Available | 14.01 | 84 | 11.17 | 23.7 | 11.26 | 90 |
| 2005 Average | 7.33 | 8.67 | 12.7 | 98.2 | 11.34 | 82.1 | 8.56 | 24 | 8.47 | 91.3 |
| 2006 January | 8.02 | 10.8 | 14.94 | Not Available | 14.15 | 84 | 10.84 | 23.8 | 9.15 | 93.9 |
| 2006 February | 6.86 | 9.34 | 14 | Not Available | 12.95 | 84.2 | 9.35 | 23.9 | 8 | 95.5 |
| 2006 March | 6.44 | 8.81 | 13.19 | Not Available | 12.07 | 83.9 | 8.23 | 24 | 7.36 | 94.7 |
| 2006 April | 6.38 | 8.29 | 13.29 | Not Available | 11.57 | 80.8 | 7.91 | 23.6 | 7.32 | 94.7 |
| 2006 May | 6.24 | 7.99 | 14.43 | Not Available | 11.6 | 78.4 | 7.62 | 23.9 | 6.89 | 93 |
| 2006 June | 5.78 | 7.39 | 15.09 | Not Available | 11.09 | 75.7 | 6.9 | 23.5 | 6.69 | 93.8 |
| 2006 July | 5.92 | 7.4 | 15.73 | Not Available | 10.98 | 74.3 | 6.77 | 23.8 | 6.69 | 92.8 |
| 2006 August | 6.56 | 8.1 | 16.19 | Not Available | 11.2 | 72.4 | 7.35 | 23.8 | 7.56 | 91.9 |
| 2006 September | 6.06 | 7.68 | 15.73 | Not Available | 11.16 | 74.5 | 7.2 | 22.2 | 6.27 | 93.6 |
| 2006 October | 5.09 | 6.42 | 12.52 | Not Available | 10.04 | 77.2 | 5.62 | 23 | 5.76 | 92 |
| 2006 November | 6.72 | 8.47 | 12.47 | Not Available | 11.05 | 80.2 | 7.74 | 23.1 | 7.48 | 93.9 |
| 2006 December | 6.76 | 8.66 | 12.54 | Not Available | 11.61 | 82.6 | 8.23 | 23.5 | 7.57 | 93.7 |
| 2006 Average | 6.4 | 8.61 | 13.75 | 98.1 | 11.99 | 80.7 | 7.86 | 23.5 | 7.11 | 93.4 |
| 2007 January | 5.92 | 7.89 | 12.09 | Not Available | 11.14 | 83 | 7.34 | 22 | 7.05 | 95.7 |
| 2007 February | 6.66 | 8.59 | 12.12 | Not Available | 11.24 | 83.7 | 8.23 | 22.1 | 8.16 | 92.5 |
| 2007 March | 6.56 | 8.81 | 12.86 | Not Available | 11.82 | 83.3 | 8.4 | 21.7 | 7.64 | 93.7 |
| 2007 April | 6.84 | 8.19 | 13.27 | Not Available | 11.51 | 80.9 | 8.14 | 21.9 | 7.76 | 94.6 |
| 2007 May | 6.98 | 8.35 | 14.61 | Not Available | 11.51 | 77.8 | 8.11 | 22.6 | 7.96 | 94.1 |
| 2007 June | 6.86 | 8.4 | 16.2 | Not Available | 11.87 | 73.6 | 7.99 | 23.2 | 7.8 | 94.1 |
| 2007 July | 6.19 | 7.95 | 16.65 | Not Available | 11.63 | 73.9 | 7.56 | 22.5 | 7.01 | 93 |
| 2007 August | 5.9 | 7.46 | 16.64 | Not Available | 11.18 | 72 | 6.58 | 22.2 | 6.8 | 88.1 |
| 2007 September | 5.61 | 6.9 | 15.94 | Not Available | 10.9 | 72.1 | 6.12 | 22 | 6.35 | 94.7 |
| 2007 October | 6.25 | 7.36 | 14.25 | Not Available | 10.8 | 69.2 | 6.86 | 22.4 | 7.04 | 94.7 |
| 2007 November | 6.37 | 8.05 | 12.82 | Not Available | 11.04 | 74.4 | 7.64 | 21.4 | 7.27 | 94.1 |
| 2007 December | 6.53 | 8.13 | 12.17 | Not Available | 11.02 | 78.3 | 7.99 | 22 | 7.93 | 94.1 |
| 2007 Average | 6.39 | 8.11 | 13.01 | 97.9 | 11.31 | 79.1 | 7.59 | 22.2 | 7.31 | 93.2 |
| 2008 January | 6.99 | 8.34 | 12.1 | Not Available | 11.06 | 79 | 8.19 | 20.5 | 8.48 | 99.6 |
| 2008 February | 7.55 | 8.87 | 12.44 | Not Available | 11.35 | 78.6 | 8.92 | 20.4 | 8.9 | 101.9 |
| 2008 March | 8.29 | 9.45 | 12.97 | Not Available | 11.78 | 78.4 | 9.63 | 21.3 | 9.56 | 99.7 |
| 2008 April | 8.94 | 9.86 | 14.3 | Not Available | 12.45 | 75.5 | 10.02 | 21.8 | 10.27 | 100.8 |
| 2008 May | 9.81 | 10.96 | 16.02 | Not Available | 13.23 | 71.5 | 11.33 | 21.3 | 10.96 | 99.3 |
| 2008 June | 10.82 | 11.72 | 18.32 | Not Available | 14.41 | 70.8 | 12.07 | 20.9 | 12.6 | 98.3 |
| 2008 July | 10.62 | 12.37 | 20.2 | Not Available | 15.43 | 66.9 | 13.07 | 20.7 | 12.16 | 97.1 |
| 2008 August | 8.32 | 10.16 | 19.63 | Not Available | 14.06 | 65.4 | 9.95 | 20.3 | 9.33 | 97.8 |
| 2008 September | 7.27 | 8.96 | 17.94 | Not Available | 13.04 | 65.3 | 8.91 | 18.5 | 8.03 | 99.5 |
| 2008 October | 6.36 | 7.88 | 15.23 | Not Available | 11.82 | 68.8 | 8.08 | 18.8 | 6.83 | 99.4 |