I need to add an account aging set of columns to an existing detail report. I believe I have the formulas but am not sure how to get the information into the cursor (or from the cursor) that is used to generate the report...

Here are the formulas - this assumes payments pay off oldest debt

KEY: Ax = Aging total due
Cx = Charges for that period
Px = Payments for that period
PT = Total of payments for all periods

90+ If PT > C90 then A90=0, PT=PT-C90 else A90=C90-PT, PT=0
60 If PT > C60 then A60=0, PT=PT-C60 else A60=C60-PT, PT=0
30 If PT > C30 then A30=0, PT=PT-C30 else A30=C30-PT, PT=0
Cur A30=C0-PT

I use SUM in the SELECT to get the Cx & Px totals. The problem I am having is that I am not sure how to handle the double "math" that is needed for each side of the IF so that I get the right amounts as I work through all the formulas.

Suggestions?