DSum syntax for report

[dwilson]

DSum function in report
Can anyone tell me what is wrong with the syntax in this formula in the report footer on my report?
I keep getting an error

=DSum("[HP Paid]","PEST","[SERVICE TYPE PEST]=True")

I have a query named PEST that this report is based on
I want to sum field HP Paid(currency type field) where the field SERVICE TYPE PEST has a check (it's a Yes/No field)


I have used DCOUNT functions quite a bit but never tried DSUM.

[rpeare]

=DSum("[HP Paid]","PEST","[SERVICE TYPE PEST]=-1")

Yes/No fields are stored as -1 for yes, 0 for no

[dwilson]

Found syntax that works:
=Sum(IIf([SERVICE TYPE PEST]=True,[HP Paid],0))