Figure 2,,
Modal Shares of U.S  Goods Trade with NAFTAPartners by Value and Weight: 2006,,
,Value,Weight
Truck, 61.6 , 26.3 
Rail, 14.9 , 20.6 
Water, 8.1 , 34.6 
Pipeline, 6.6 , 13.1 
Other and unknown, 4.7 , 5.3 
Air, 4.1 , 0.1 
NOTE: 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, March 2007.",,