U.S. intermodal traffic rose 4.1% last week from a year ago, the Association of American Railroads reported.
Container traffic for the week ended Saturday rose 6.3% to 220,142 units, while trailers fell 9.9% to 30,177 units.
Railroad carloads excluding intermodal slipped 1.5% to 288,167 units, AAR said.
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.