Railroads. Freight and passenger train service unit costs (selected expense accounts) Of class 1 steam roads in United States, including proportion of mixed-train and special-train service (compiled from 161 reports representing 1.77 steam roads, switching and terminal companies not included), Oct. 1922 and 1921, and 10 months rended with Oct.] 1922 and 1921; [prepared in] Bureau of Statistics.