Using a formula to show a negative value in a Summary report

Greetings all,

I have a table with a Port Type (Port In or Port Out) text field and Carrier text field. I have built a summary report summarizing the port type (ports in and ports out) by carrier.

For the ports out, I want to have that be a negative number so my totals column ends up showing a net of ports in and out.

I tried to build a report formula using an IF statement to make Ports Out negative: -(If([Port Type]="Port Out", 1)). However, that didn't work. Then I tried to define summary variables for Ports In and Ports Out summarized by totals then write a summary report formula subtracting ports out from ports in, but still no luck.

Can anyone tell me if what I want to do is possible using summary report formulas or do I need to go about it a different way?

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Doug Crandall
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