Calculate Difference for Groups

[sid78669]

I have a table for Account Transaction. For each transaction a user must select a transaction category. These are stored in a second table which has a categoryID, description and a text box with only two values {'Income', 'Expense'}.

Now in the report, I am grouping by Income/Expense. However, I want to be able to calculate the sub-totals of incomes and expenses and then show what the difference is. I am able to calculate the subtotals, but have no idea how to calculate the difference. Ideas?

[BitBlt]

Create a separate text box in the footer; point its record source to be the totals text boxes you have previously calculated.