NOTE: The 2001
National Household Travel Survey “travel period” data were not
available when this report was prepared. Without these data, vacation trips
and travel by air tend to be underrepresented.
SOURCE: 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.
