Crosstab Intersection Calculation

[bfmooz]

I'm hoping someone has come across this issue and knows a way to address it.

I have a crosstab report.  Across the columns, I have dropped in Months.  Down the rows, I have static members of an Accounts hierarchy.  I have a measure intersecting them for Period Amount.

For the Accounts, there are certain one where a sign reversal needs to be done, e.g. Total Sales.  So for example, the measure intersecting Month 1 and Total Sales needs to equal Period Amount X (-1), but the measure intersecting Month 1 and Total Cost of Sales needs to equal Period Amount.

Any suggestions on how this could be done given that I am using static members down the rows?