Nelson,
you asked earlier about PFE traffic in the upper Midwest, I have just uploaded a file - NP Reefer traffic Twin Cities Nov 9, 1947. Hope this shines some light.
I realize the dates between Clark's data and mine differ by about fives years however it is what was found at one time. And it looks like I need to purchase some PFE reefers. I was honestly surprised.
Tim O'Conner prior, was good enough to list four excellent PFE reefers readily available and Dick Harley added some frosting to that cake on STMFC post 129871.
I have uploaded the file in a word doc and as a PDF. The word doc is open (I hope) to someone doing the percentages. I will openly admit, I am not a math wiz. Jim Dick - Roseville, MN