Help with Cross tab grand total

[Durango122]

Hi All
cr 9.0
ms sql
i have a cross tab
i created a group base on trade_class and order by S and R and i need to get grand total at bottom of report footer
i have a formula that breaks it down by trade_class
here is my formula
---------------------------
@RorS
if
{TRANSACTION_HISTORY.TRADE_CLASS} = 'S'
then
'Contributions'
else
'Redemptions'
----------------------------------
Here is how it built
------------------------------------------------------
CrossTab

Rows:
portfolio
@RorS
Column:
year
month
Summarize:
sum of @Amount

here is how it looks

---------------------------------------------------------
Gr#1
*******************************2007
--------------------------jan-----feb----mar
age base 0-3|Contribution|500-----500----300
age base 4-6|Contribution|500-----200----100
total Contribution-------|1000----700----400
age base 7-8|Redemption--|-200****-200***-100
age base 9-10|Redemption-|-100****-100***-200
total Redemption---------|-300****-300***-300
--------------------------------------------------
Report Footer
Net contribution********|1400*****800****200

i need to substract the Contribution total minus the redemption total

not sure if possible with cross tab because i need to get the total from the cross tab

any help would be great

thanks




Durango122
if it moves and should not used Duck Tape
if does not move and should used WD-40