IntroductionCompiled and published by the U.S. Department of Transportation's Bureau of Transportation Statistics (BTS), National Transportation Statistics presents information on the U.S. transportation system, including its physical components, safety record, economic performance, energy use, and environmental impacts. National Transportation Statistics is a companion document to the Transportation Statistics Annual Report, which analyzes some of the data presented here, and State Transportation Statistics, which presents state-level data on many of the same topics presented here. The report has four chapters:
Appendix A contains metric conversions of select tables. BTS obtained the data in this report from many sources, including federal government agencies, private industry, and associations. Documents cited as sources for the tables provide detailed information about definitions, methodologies, and statistical reliability. Some of the data are based on samples and are subject to sampling variability. National Transportation Statistics is updated quarterly at www.bts.gov. Find this web page at:
http://www.bts.gov/publications/national_transportation_statistics/2008/html/introduction.html |