Rail intermodal traffic fell 5.2% for the week ended Saturday compared with a year ago, the Association of American Railroads said.
Container traffic fell 4% to 163,862 units, while trailer traffic plunged 9.2% to 47,052 units, AAR said in its weekly report issued Thursday.
Overall rail carload traffic fell 3.3% to 323,536 carloads, the group 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.