Table 9,,,,,
"Number of Aircraft, Railcars, Vehicles, and Vessels",,,,,
Mode,1970,1980,1990,2000,2001
Air carriers,"2,679","3,808","6,083","8,055","8,497"
General aviation,"131,743","211,045","R196,800","217,533",U
Passenger carsa,"89,243,557","121,600,843","133,700,496","133,621,420","137,633,467"
Motorcycles ,"2,824,098","5,693,940","4,259,462","4,346,068","4,903,056"
"Other 2-axle, 
4-tire vehicles","14,210,591","27,875,934","48,274,555","79,084,979","84,187,636"
Trucks,,,,,
Single-unit,"3,681,405","4,373,784","4,486,981","5,926,030","5,703,500"
Combination,"905,082","1,416,869","1,708,895","2,096,619","2,154,174"
Busesb,"377,562","528,789","626,987","746,125","749,548"
Passenger rail: ,,,,,
Amtrak—Cars,N,"2,128","1,863","1,894",U
Locomotives,N,419,318,378,U
Commuter railcars and locomotives,N,"4,500","4,415","P5,073 ",U
Transitc,"10,548","10,654","11,332","P12,168 ",U
Class I rail:,,,,,
Freight cars,"1,423,921","1,168,114","658,902","560,154","499,860"
Locomotives,"27,077","28,094","18,835","20,028","19,745"
Other freight cars,"360,260","542,713","553,359","820,642","814,276"
"Nonself-propelled vessels d,e","19,377","31,662","31,209","33,152",U
Self-propelled vesselse,"6,455","7,126","8,236","8,202",U
"Oceangoing shipse
(1,000 gross tons and over)","1,579",864,636,R454 ,443
Recreational boatsf,"R5,128,345","8,577,857","10,996,253","12,782,143","12,884,166"
"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 See glossary.   
e U.S.-flag vessels.  
f Numbered boats.    ",,,,,
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Key: N = data do not exist; P = preliminary; U = unavailable; R = revised.,,,,,
"Sources: Various sources, as cited in USDOT, BTS, National Transportation Statistics 2002 (Washington, DC: 2002); table 1-9; air carriers 2000–2001—Aerospace Industries Association, Aerospace Facts & Figures (Washington DC: 2002/2003), ""Active U.S. Air Carrier Fleet""; 2001 Class I rail—Association of American Railroads, Class I Railroad Statistics, available at http://www.aar.org/ AboutTheIndustry/AboutThe Industry.asp, as of Oct. 2002; oceangoing ships 2000–2001—USDOT, Maritime Administration, Office of Statistical & Economic Analysis, personal communication, 2002; recreational boats 2001—U.S. Coast Guard, personal communication, 2002.",,,,,
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