Rail carload and intermodal traffic fell for last the first week of 2008 compared with the same week last year, the Association of American Railroads said.
Intermodal traffic plunged 13.1% to 163,801 trailers and containers, AAR said in its weekly report released Thursday.
Container volume fell 12.6% to 130,083 units, while trailers plunged 15% to 33,718 units.
Overall rail carload traffic fell 3.2% from a year ago to 277,741 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.