Freight carload traffic on U.S. railroads declined 12.1% in the week ending Jan. 5 from the year-ago level, and intermodal dropped 8%, according to the Association of American Railroads. However, petroleum shipments rose 53.6% and "traffic volume was likely impacted by the New Year's holiday, which fell on a Monday and Tuesday in 2013, as opposed to Saturday and Sunday in 2012," AAR noted.