Intermodal traffic rose 18.1% last week from a year earlier, the Association of American Railroads said Thursday.
Traffic for the week ended Saturday totaled 206,850 trailers and containers, led by a 20.7% jump in containers to 178,338 units, the group said.
Trailers rose 4.1% to 28,512 units. Container volume was down 4.6% from the same week in 2008, while trailer volume was 43% lower.
U.S. railroads originated 277,530 carloads for the week, 5.1% higher than a year ago, AAR said in its weekly report.
That was down from 305,000 the week before, which had been the second straight weekly high for 2010, and 15.5% below the same week in 2008.
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.