It appears based on the information that i find that it is not possible to calculate subtotals in a cross-tab report. In a list report I can take a total and wrap it in an if statement like so
if ([ACCOUNT_TYPE] = '50') THEN
([YEAR_TO_DATE_ACTIVITY])
ELSE
([YEAR_TO_DATE_ACTIVITY] *-1)
If I try that in a Crosstab I get the following error
OP-ERR-0118
The dimensions on the edge are inconsistent. The dimension of valueSet="2" differs from the dimension of sibling edgeGroups.
Can anyone confirm this is true or provide an example of how to do this?