I am setting up a monthly report that summarizes a activity for a month. I have setup a date range form and I can pass those values to a parameterized query for the reports data source.

But how would I be able to run a sum against a dollar amount column based on a yes/no column in the table. Ex. I want to sum up all approved amounts where the column Food Assistance is yes (this is for just the date range). This needs to happen several time in the report for different yes/no fields in the table. Can you shed any light on this?

=Sum(Iif([YourYes/NoField],[YourDollarField],0))

I tried the following expression:
=Sum(IIf([CRTMRDSS],[CRTMRDSSAmount],0))

Where CRTMRDSS is a yes/no and CRTMRDSSAmount is the dollar amount that i want to sum and I get a #Error when I run the report. I have added the two fields to my query that the report uses. Any ideas?