Btu per passenger-mile
| Passenger cars | Light-duty trucks | Transit buses | Aircraft (domestic) | Amtrak | |
|---|---|---|---|---|---|
| 1998 | 3,637 | 4,569 | 3,646 | 4,123 | 2,255 |
| 1999 | 3,672 | 4,612 | 3,546 | 4,049 | 2,344 |
| 2000 | 3,589 | 4,509 | 3,618 | 3,883 | 2,688 |
| 2001 | 3,597 | 3,985 | 3,492 | 3,848 | 2,690 |
| 2002 | 3,600 | 4,121 | 3,308 | 3,609 | 2,537 |
| 2003 | 3,570 | 4,452 | 3,201 | 3,496 | 2,145 |
| 2004 | 3,509 | 4,452 | 3,240 | 3,410 | 2,068 |
| 2005 | 3,585 | 4,077 | 2,685 | 3,232 | 2,025 |
| 2006 | 3,510 | 4,042 | 2,882 | 3,142 | 1,948 |
| 2007 | 3,518 | 4,008 | 2,771 | 3,040 | 1,824 |
| 2008 | 3,501 | 3,980 | 2,656 | 2,931 | 1,745 |
KEY: Btu = British thermal unit.
SOURCES: Aircraft: Research and Innovative Technology Administration, Bureau of Transportation Statistics; Passenger cars and Light-duty trucks: Federal Highway Administration; Transit buses: Federal Transit Administration, National Transit Database; Amtrak: National Railroad Passenger Corporation (Amtrak) as cited in U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics, National Transportation Statistics, table 4-20, available at http://www.bts.gov/publications/national_transportation_statistics/ as of April 2010.