4-2,,,,
"Number of Aircraft, Railcars, Vehicles, and Vessels: 1980–2005",,,,
Mode,1990,2000,2004,2005
Air,,,,
Air carrier,"6,083","8,055","8,186","8,225"
General aviation,"198,000","217,533","219,426","224,352"
Highway,,,,
Automobiles,"133,700,496","133,621,420","136,430,651","136,568,083"
"Other 2-axle, 4-tire vehiclesa","48,274,555","79,084,979","91,845,327","95,336,839"
"Buses (municipally owned transit and commercial, federal, and school buses)","626,987","746,125","795,274","807,053"
Motorcycles ,"4,259,462","4,346,068","R5,767,934","6,227,146"
Trucks,,,,
Single-unit,"4,486,981","5,926,030","6,161,028","6,395,240"
Combination,"1,708,895","2,096,619","2,010,335","2,086,759"
Rail—Passenger,,,,
Amtrak–Cars,"1,863","1,894","1,211","1,186"
Amtrak–Locomotives,318,378,276,258
Commuter railcars and locomotives ,"5,007","5,498","6,228","P6,392"
Transitb,"11,332","12,168","12,480","P12,755"
Rail—freight,,,,
Class I–Freight cars,"658,902","560,154","473,773","474,839"
Class I–Locomotives,"18,835","20,028","22,015","22,779"
Other freight cars,"553,359","820,642","814,147","837,461"
Waterborne,,,,
"Nonself-propelled vessels (barges)c,d","31,209","33,152","31,296","32,052"
"Self-propelled vesselsc,d","8,236","8,202","8,994","8,976"
"Oceangoing shipsd (1,000 gross tons and over)    ",636,454,412,357
Recreational boats (numbered boats),"10,996,253","12,782,143","12,781,476","12,942,414"
"a Includes vans, pickup trucks, sport utility vehicles, and other 2-axle, 4-tire motor vehicles that are not passenger cars.   ",,,,
b Includes light and heavy rail transit only.   ,,,,
c See Glossary for definitions.   ,,,,
d U.S.-flag vessels.   ,,,,
Key: P = preliminary; R = revised.,,,,
"Sources: Except as noted, various sources, as cited in U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics, National Transportation Statistics, table 1-11, available at http://www.bts.gov as of September 2007.",,,,