Table 4. U.S. Merchandise Trade with Canada by Surface Modes of Transportation,,,,,, (millions of dollars),,,,,, Mode,,September 2005,August 2006,September 2006,Percent Change Aug. 2006-Sept. 2006,Percent Change September 2005-2006 All Surface Modes,Imports,"23,659","23,924","22,916",-4.2,-3.1 ,Exports,"16,711","18,299","17,488",-4.4,4.7 ,Total,"40,370","42,223","40,404",-4.3,0.1 ,,,,,, Truck,Imports,"12,573","12,730","12,674",-0.4,0.8 ,Exports,"13,217","14,269","13,789",-3.4,4.3 ,,,,,, Rail,Imports,"5,258","5,438","4,832",-11.1,-8.1 ,Exports,"1,578","2,041","1,885",-7.6,19.4 ,,,,,, Pipeline,Imports,"4,681","4,872","4,180",-14.2,-10.7 ,Exports,82,114,140,22.2,70.8 "Source: BTS Transborder Freight Data, 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 Freight Data ""Sources and Reliability"" statement: http://www.bts.gov/ntda/tbscd/srfin.html; Numbers may not add to totals due to rounding.",,,,,,