(Thousands of short tons)
a The weight data for water transportation vary from those officially reported by the U.S. Army Corps of Engineers, because the data in this table exclude intransit shipments (merchandise shipped from one foreign country to another via a U.S. port but not part of U.S. official merchandise trade). BTS uses Census Bureau trade-based data to allow for a complete modal comparison among the different freight transportation modes.
b BTS estimated the export weight for truck, rail, pipeline, and other and unknown based on value-to-weight ratios from the import data by country, mode of transportation, and two digit HS commodity code. This was necessary, because export weights for surface modes are not currently reported. Weight for water and air exports and imports are from U.S. Department of Commerce, U.S. Census Bureau.
Notes: Numbers may not add to totals due to rounding.
Water-Excludes intransit data (merchandise shipped from one foreign country to another via a U.S. water port).
Imports-Excludes imports valued at less than $1,250. Import value is based on U.S. general imports, customs value basis.
Exports-Excludes exports valued at less than $2,500. Export value is FAS (free alongside ship) and represents the value of exports at the port of export, including the transaction price and inland freight, insurance, and other charges.
Sources: Compiled by U.S. Department of Transportation (USDOT), Research and Innovative Technology Administration (RITA), Bureau of Transportation Statistics (BTS), September 2006. Water and air data-U.S. Department of Commerce, U.S. Census Bureau, Foreign Trade Division, U.S. Exports of Merchandise, CD-ROM and U.S. Imports of Merchandise, CD-ROM, December 2005. Total, truck, rail, pipeline, other and unknown data-USDOT, RITA, BTS, Transborder Freight Data 2005; and special calculation, September 2006.