A new Transportation Department report shows trucks carried more U.S. freight by value with its North American Free Trade Agreement partners, Canada and Mexico, in May compared to the year before. But declines in all other freight modes led to a 3.1% decrease in the dollar value of cross-border freight, totaling $89 billion.

May was also the 17th consecutive month that the total value of U.S.-NAFTA freight declined from the same month the year before.

The value of commodities moving by truck increased 1.3% as the value of incoming freight from Mexico, up 6.2 %, and Canada, up 11.4%, exceeded the 5.5% decrease in shipments from the U.S.

Of the top 10 commodities transported between the U.S. and other NAFTA countries by truck, fruits and nuts had the highest year-over-year increase-- 13.2%.

The value of freight carried by other modes, rail, pipeline and vessel all, declined. That was due in large part to a drop in the dollar value of crude oil shipped by the latter two modes.

Trucks carried 66% of U.S.-NAFTA freight and continued to be the most heavily utilized mode for moving goods to and from both U.S.-NAFTA partners. Trucks accounted for $31.2 billion of the $47.9 billion in imports, 65.3%, and $28.1 billion of the $42 billion in exports, or 66.9%. Rail remained the second largest mode by value, moving 15.8% of all U.S.-NAFTA freight.

Freight Movement Value with Canada Declines

The value of U.S.-Canada freight flows fell 6% in May compared to a year earlier to $46 billion as all modes of transportation except truck carried a lower value of U.S.-Canada freight, due again to lower crude oil prices.

The top commodity category transported between the U.S. and Canada by all modes was vehicles and parts, of which $5.1 billion, or 55.2%, moved by truck and $3.9 billion, or 42.4%, moved by rail.

Trucks carried 61.1% of the value of the freight to and from Canada while rail carried 16.6%.

Freight Flows with Mexico Edge Slightly Higher

The value of U.S.-Mexico freight rose 0.1% in May vs. May 2015, hitting $43.9 billion, as all modes of transportation except truck and rail carried a lower value of U.S.-Mexico freight than a year earlier. Freight carried by truck and rail each increased 2.3%.

Trucks carried 71.2% of the value of freight to and from Mexico while rail carried 15%.

The top commodity category transported between the U.S. and Mexico by all modes in May 2016 was electrical machinery, of which $7.6 billion, or 91.6%, moved by truck.