Table 11,,,,,
Passenger-Miles,,,,,
(Millions),,,,,
Mode,1970,1980,1990,2000,2001
Air carriers,"108,442","204,368","345,873","R516,129","486,506"
General aviation,"9,100","14,700","13,000",U,U
Passenger cars,"1,750,897","2,011,989","2,281,391","R2,544,457","2,574,882"
Motorcycles ,"3,277","12,257","12,424","R11,516","10,482"
"Other 2-axle, 4-tire vehiclesa","225,613","520,774","999,754","R1,467,664","1,491,164"
Busesb,N,N,"121,398","R160,919","148,113"
Rail:,,,,,
Transitc,N,"10,939","12,046","P15,200",U
Commuter,"4,592","6,516","7,082","P9,402",U
Intercity/ Amtrakd,"6,179","4,503","6,057","5,498",U
Other transite,N,390,841,"P1,631",U
"a In July 1997, the USDOT, Federal Highway Administration, reassigned some vehicles from “passenger car” to “other 2-axle, 4-tire.” 
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, ferry boat, and other transit not specified; 1980 data include ferry boat and “other transit” only.",,,,,
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Key: N = data do not exist; P = preliminary; R = revised; U = unavailable.,,,,,
"Sources: Various sources, as cited in USDOT, Bureau of Transportation Statistics, National Transportation Statistics 2002 (Washington, DC: 2002), table 1-34. 2001 air carriers—USDOT, Bureau of Transportation Statistics, Air Carrier Traffic Statistics (Washington, DC: Annual December issues).",,,,,
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