Figure 3: Modal Shares of U.S Trade with NAFTA Partners by Value and Weight, 2007
NOTES: These data reflect U.S. import and export trade with Canada and Mexico. Weights of export shipments by land modes are not collected in the administrative records that provide U.S. trade data. The Bureau of Transportation Statistics has estimated the land mode export tonnage using value-to-weight ratios derived from imported commodities.
SOURCE: U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics, Transborder Freight Data as of March 2007.