Driving an automobile 15,000 miles per year cost 50¢ per mile in 2001, or 16 percent more than it did in 1991, when total costs were 43¢ (figure 34). These data, which are expressed in 1996 chained dollars,1 include fixed costs (e.g., depreciation, insurance, finance charges, and license fees) and variable costs (e.g., gasoline and oil, maintenance, and tires). Over the decade, fixed costs have consistently represented about 75 percent of total per-mile costs. Gasoline and oil, a component of variable costs, represented 14 percent of driving costs per mile in 2001, up from 12 percent in 2000 .
About 87 percent of the daily trips Americans took in 2001 occurred in highway vehicles, including their own automobiles . The other 13 percent traveled via public transportation or air, rode bicycles, walked, or traveled by other means.
1. American Automobile Association, Your Driving Costs (Heathrow, FL: 2000 and 2001 issues).
2. U.S. Department of Transportation, Bureau of Transportation Statistics and Federal Highway Administration, 2001 National Household Travel Survey, Preliminary Data Release Version 1 (day trip data only), available at http://nhts.ornl.gov, as of January 2003.
1 All dollar amounts are expressed in chained 1996 dollars, unless otherwise specified. Current dollar amounts (which are available in appendix B of this report) were adjusted to eliminate the effects of inflation over time.