Table 2. U.S. Merchandise Trade with Canada and Mexico by Surface Modes of Transportation,,,,,, (millions of dollars),,,,,, Mode,,May 2005,April 2006,May 2006,Percent Change Apr. 2006–May 2006,Percent Change May 2005-2006 ,,,,,, All Surface Modes,Imports,"32,503","35,126","37,257",6.1,14.6 ,Exports,"25,367","26,616","28,737",8,13.3 ,Total,"57,870","61,742","65,994",6.9,14 Truck,Imports,"21,659","22,102","24,377",10.3,12.6 ,Exports,"19,967","20,871","22,861",9.5,14.5 Rail,Imports,"6,786","7,471","7,440",-0.4,9.6 ,Exports,"3,106","3,255","3,599",10.6,15.9 Pipeline,Imports,"2,939","4,227","4,367",3.3,48.6 ,Exports,347,187,260,39,-25 "Source: BTS Transborder Surface Freight Dataset, http://www.bts.gov/transborder/",,,,,, "Note: The value of all surface modes is not equal to the sum of truck, rail and pipeline modes. The value of trade for all surface modes includes shipments made by truck, rail, pipeline, mail, foreign trade zones, other and unknown modes of transportation.  For additional detail refer to the Transborder Surface Freight data ""Sources and Reliability"" statement: http://www.bts.gov/ntda/tbscd/srfin.html; Numbers may not add to totals due to rounding.",,,,,,