In a message dated 9/23/03 11:25:08 PM, HAWK0621@... writes:

<< And hoppers were probably empty more often than they were loaded. >>

Actually, open-top hoppers, like most cars, tended to run loaded slightly
more than they ran empty. Here are some data (cited from Table 20, pg. 154, in
Healy's book "Performance of US Railroads Since WW2" who cites ICC data as his
source).

The AAR continues to publish data each year on loaded and empty car-miles by
car type in their "Green Book".

Year Percent Empty to Total Car-Miles
1948/49 43
1956/57 46
1968 47 1/2
1972 47 1/2

The only car types that he shows running slightly more car-miles empty than
loaded are tank cars and covered hoppers in certain years.

Chris Barkan