Subtracting form a total

[Kicker3]

I have a proposal table (FM7) that adds up & totals all the work I'm doing. However it dosen't subtract. If I set a discount like -$100.00 it subtract it, it adds it? My calculations are: TotalLine Calculation = Charges * Footage

then _cTotal Calculation, Unsorted,= Sum(Details::Totals) Can anyone tell me what Im' doing wrong?

[transpower]

Well, subtacting a negative number is the same as adding it.