Hi:
OK..for your SAS dataset. If you run PROC CONTENTS, do you see that $RANK is listed as the format???
If yes, then try:
library=library or
library=work
in your PROC FORMAT statement. The chances are good that your folks who built the format took the default and stored the user defined format in a format catalog called "LIBRARY" or in "WORK" -- I know, it seems redundant to have LIBRARY=LIBRARY, but that's one of the "simple" ways that folks have defined their own format catalogs over the years.
You cannot put your dataset name in the LIBRARY= option.
If you run a PROC CONTENTS and do NOT see $RANK listed as the format being used for the field, then it is probable that the format used to create the RANK variable might not be available to you.
cynthia