A donor can give 500 units every 2 months. I want to produce a report each week stating how much each donor can give that week. A Sum field in a Subsummary part based on last name will tell me how much each donor has giving during the specified time period. If I place a Calculated field of "500-Sum" in the Subsummary field with only 1 donor in the found set it will do the calculation properly using only the donations by the specified donor. If I have more than one donor in the found set, it will sum the donation of every single donor even though the Sum field for each donor is correct for that donor.
How can I make the calculation use only the Sum of the donor that the Subsummary names? In the example, Dark Knight should have 50 available and Super Man should have 200 but the program is adding 450+300 and subtracting it from 500.
If only Dark Knight is in the found set the calculation is correct:
My layout looks like this:
Is it possible for the 500-Sum to work like I want or do I need a different strategy?