Agana
, GU
|
AG
|
Alcan
, AK
|
AL
|
Anchorage
, AK
|
AN
|
Atlanta
, GA
|
AT
|
Baltimore
, MD
|
BA
|
Blaine
, WA
|
BL
|
Buffalo/Niagara Falls
, NY
|
BN
|
Boston
, MA
|
BO
|
Brownsville
, TX
|
BV
|
Calais
, ME
|
CA
|
Chicago
, IL
|
CH
|
Cleveland
, OH
|
CL
|
Champlain
, NY
|
CP
|
Calexico
, CA
|
CX
|
Detroit
, MI
|
DE
|
Dallas/Fort Worth
, TX
|
DF
|
Douglas
, AZ
|
DG
|
Derby Line
, VT
|
DL
|
Denver
, CO
|
DN
|
Del Rio
, TX
|
DR
|
Dunseith
, ND
|
DS
|
Washington Dulles
, VA
|
DU
|
Eastport
, ID
|
EA
|
El Paso
, TX
|
EL
|
|
Fairbanks
, AK
|
FB
|
Grand Portage
, MN
|
GP
|
Honolulu
, HI
|
HA
|
Houston
, TX
|
HN
|
Houlton
, ME
|
HO
|
Highgate Springs
, VT
|
HS
|
International Falls
, MN
|
IF
|
Jackman
, ME
|
JK
|
Juneau
, AK
|
JU
|
Los Angeles
, CA
|
LA
|
Lukeville
, AZ
|
LK
|
Louisville
, KY
|
LO
|
Laredo
, TX
|
LR
|
Las Vegas
, NV
|
LV
|
McAllen
, TX
|
MC
|
Memphis
, TN
|
ME
|
Miami
, FL
|
MI
|
Minneapolis./St. Paul
, MN
|
MP
|
Norfolk
, VA
|
NF
|
Nogales
, AZ
|
NG
|
New Orleans
, LA
|
NO
|
Newark
, NJ
|
NW
|
New York
, NY
|
NY
|
|
Philadelphia
, PA
|
PA
|
Pembina
, ND
|
PB
|
Port Huron
, MI
|
PH
|
Portal
, ND
|
PL
|
Portland
, OR
|
PT
|
Phoenix
, AZ
|
PX
|
Raymond
, MT
|
RY
|
Seattle
, WA
|
SE
|
San Francisco
, CA
|
SF
|
San Juan
, PR
|
SJ
|
San Luis
, AZ
|
SL
|
Saipan
, MP
|
SP
|
Sault Sainte Marie
, MI
|
SS
|
Sumas
, WA
|
SU
|
Sweetgrass
, MT
|
SW
|
San Diego/San Ysidro
, CA
|
SY
|
Tampa
, FL
|
TP
|
Unknown
|
XX
|
|