Summary Table in a BAQ

I created a BAQ for AR - I have Invcdtl with part info but, I want to summarize Total(AdvanceBillingTotal.AdvanceBillCredit).

Anyway, I created a Calculated field where AdvancedBilling <> 0 then … Else 0

I also used the > sign.

The Invoice I am using for my test has an advanced Billing Total of $42,400.

However, my calculated field is not behaving. All I get is 0.

Any ideas