Intermodal traffic rose 0.6% for the week ended Saturday from a year ago, led by an increase in trailer traffic, the Association of American Railroads said.
Container traffic edged up 0.4% to 179,401 units from a year ago, while trailer traffic climbed 2.2% to 28,689 units.
Railroad carloads excluding intermodal increased 0.1%, to 278,382 units, AAR said in its weekly report.
Railroad volume is considered an important economic indicator. Intermodal traffic, which tends to be higher-valued merchandise than bulk commodities, uses trains for the long haul and trucks for the shorter distance at either end of the trip.