I'd like to know how much TOFC traffic accounts for total rr traffic these days? I am assuming TOFC is what is leading to the abandonment of branch lines and factory spurs.
try this link to Railway Age, there is a table of car load and intermodal statistics.
Of note, "Trailers" account for about 30% of the Intermodal business on the US railroads, with the balance being containers.
http://www.railwayage.com/A/traffic.html