U.S. trade with its next-door neighbors totaled $101.5 billion in March 2014, the second highest amount on record, as four of five transportation modes carried more freight than the same time a year ago, according to a new U.S. Transportation Department report.

The March 2014 trade total, a 6.2% increase from March 2013, was exceeded only by trade value in October 2013. U.S-NAFTA trade has increased from the same month of the previous year in eight of the last nine months, interrupted by a 0.2% decrease in January, due to severe weather in the northern states and along the U.S.-Canada border.

In March, commodities moving by pipeline grew the most of any mode, 25.2%, while truck freight rose 6.3% and rail declined 5.2% from year to year. Trucks carried 60.1% of U.S.-NAFTA trade in March, accounting for $31.2 billion of exports and $29.8 billion of imports. 

Trade with Canada

Year-to-year, the value of U.S.-Canada trade by pipeline increased the most of any mode, growing 25.2%. Trade using trucks rose by 2.7%. U.S.-Canada trade by rail declined 10.5%, with a 15% decline in imports, due in part to a decrease in trade of vehicles and parts.

Trucks carried 54.3% of the $56.6 billion of freight to and from Canada, followed by rail at 15.4%. The surface transportation modes of truck, rail and pipeline carried 83.7% of the total U.S.-Canada freight flows.

Trade with Mexico

With U.S.-Mexico trade more dependent on trucks than trade with the northern border, a 10.2% jump in truck freight fueled the overall 8.8% increase in southern border trade. Shipments by truck comprised 77.4% of the dollar value of the overall increase. For exports, a 14.1% increase in shipments using trucks made up 86% of the overall 10.7% increase.

Year-to-year, the value of trade by pipeline increased the most of any mode, growing 25.7 percent, but pipeline trade remained less than 1% of total U.S.-Mexico trade and the smallest of the modes based on value.

Trucks carried 67.4% of the $44.9 billion of freight to and from Mexico, followed by rail at 14%. The surface transportation modes of truck, rail and pipeline carried 82.3% of the total U.S.-Mexico freight