Running Total Issue

Good Day to All,

Hopefully I can explain this so that I get a good result.

In the Running Total Dialogue box here are my entries.

Running Total Name is PriorBalance

The field that I am summarizing is @Prior and the type is SUM

and I'm Evaluateing on a group called @TranGroup-A and resetting on a change of group called ChargeType.

This is working as excepted.

My question is there a way to Evaluate on 2 criterias ?

I want to evaluate on @TranGroup and use a formula where @Prior is less than zero "{@Prior} < 0"

Or can a formula be written where it evaluates when

{@Prior} < 0 and @TranGroup --I get an error when AI try this.

Kind Regards,

David