Yes, this can be done, with an IF/THEN of the following type (using the Coffee Chain sample db):
IF ATTR([Product Type]) = "Coffee" THEN
SUM([Sales])/TOTAL(SUM(IF [Product Type] = "Coffee" THEN [Sales] ELSE 0 END))
The Compute along for this table calculation will need to be set to Table Across then Down. You can see this in the attached workbook.
different denominators.twbx.zip 170.5 KB
Thank you so much! I was able to use this base calc and expand on it to get the correct %'s for every line.