|Other 2-axle, 4-tire vehiclesa||225,613||520,774||999,754||1,467,664||1,719,750|
a Includes vans, pickup trucks, sport utility vehicles, and other 2-axle, 4-tire vehicles that are not passenger cars.
b Includes municipally owned transit, commercial, federal, and school buses.
c Includes light and heavy rail only.
d Fiscal year data. Amtrak began operations in 1971.
e Includes demand responsive, ferryboat, and other transit not specified; 1980 data include ferryboat and "other transit" only.
Key: N = data are nonexistent; P = preliminary; U = unavailable.
Sources: Except as noted, various sources, as cited in U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS), National Transportation Statistics, table 1-37, available at http://www.bts.gov (latest data forthcoming).
2002 air carriers-USDOT, BTS, Air Carrier Traffic Statistics (Washington, DC: Annual December issues), p. 2, line 1.