AAR said 11 of the 20 carload commodity groups it measures posted increases from the comparable week in 2010. Gaining groups were led by metallic ores, up 33.8%, lumber and wood products, up 17.8%, and pulp, paper, and allied products, up 12.2%. Among the declining groups, primary forest products fell 14.3%, while waste and nonferrous scrap fell 13.7%.

Canadian freight carload traffic rose a robust 4.6% from last year, but intermodal volume declined by 3.3% for the week. Mexican freight carload volume fell 3.2% for thw eek, but intermodal gained 18.9% over the same period one year ago.

Combined North American freight carload volume for the first 23 weeks of 2011 on 13 reporting U.S., Canadian, and Mexican railroads was up 2.8% compared with a year ago, while combined intermodal was up 7.5%.