calculation to find the difference between two crosstab cells in the same column

[AnandKK]

Hi,

I need to show the difference between two crosstab cells values in the same column. Imagine different calculations for Actuals, Forecast and etc

Year           2015                                    2016
               Act, Forecast,   XXX           Act, Forecast,   XXX
Revenue  20 , 30, 10%                         20,30,10%
SZB          20,40,20%                          30,60,20%
Margin     20,40.10%                            -------------------

for 2016, we need to show the  difference between Revenue and Margin.

Please suggest me.

[Francis aka khayman]

 Year           2015                                    2016
               Act, Forecast,   XXX           Act, Forecast,   XXX
Revenue  20 , 30, 10%                         20,30,10%
SZB          20,40,20%                          30,60,20%
Margin     20,40.10%                            -------------------
Rev-Mar  0,-10,xxxx


[Rev-Mar] = [Revenue] - [Margin]