Rail and intermodal traffic fell for the week ended Saturday compared with the same week a year ago, the Association of American Railroads said.
Intermodal traffic fell 0.7%, AAR said in its weekly report. Container traffic fell 1.2% to 160,804 units, while trailers rose 1% to 43,234 units.
Overall rail traffic fell 0.9% for the week, to 316,881 carloads, the group said.
For the month of May, intermodal fell by 0.9%, while rail carloads rose 0.5% year-over-year, 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.