|U.S.-NAFTA trade, totala||100.0||100.0|
|Other and unknown||4.9||0.2|
|U.S.-NAFTA imports, total||100.0||100.0|
|Other and unknown||3.3||0.1|
|U.S.-NAFTA exports, totala||100.0||100.0|
|Other and unknown||7.0||0.5|
a BTS estimated those weights for truck, rail, pipeline, and other and unknown based on value-to-weight ratios from the import data because export weights for surface modes are not currently reported. Weight for water and air exports and imports are from the U.S. Department of Commerce, U.S. Census Bureau.
Notes: Value based on millions of U.S. dollars; weight based on millions of short tons.
U.S.-NAFTA (North American Free Trade Agreement) refers to U.S. trade with Canada and Mexico, our partners in this agreement.
Sources: Compiled by U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS). 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 2003. Total, truck, rail, pipeline, other and unknown data-USDOT, BTS, Transborder Surface Freight Data 2003; and special tabulation, October 2004.