AAR also said 16 of the 20 carload commodity groups it tracks posted increases compared with the same week in 2011, led by metallic ores, up 63.2%, motor vehicles and equipment, up 42%, and petroleum products, up 40.5%. Leading the declining commodity groups was grain, down 9.7%.

Canadian freight carload volume rose 13.5% compared with the same week in 2011, while Canadian intermodal volume also did well, up 15.4%. Mexican freight carload volume bucked the positive trend in North America, slipping 0.4% for the week compared with a year ago. Mexican intermodal volume fared better, up 19.1%.

Combined North American freight carload volume for the first five weeks of 2012 on 13 reporting U.S., Canadian, and Mexican was up 1.6% measured against the same period in 2011, while intermodal rose 5.2% over the 2011 period.