working with Crosstab in cognos report studio

[sepusav]

Hello,
   I working with crosstab report in c10 Report studio.
I have a very complex issue in there,
PFA for the crosstab(mock-up). I need help I calculating YTM Growth:(CY-PY)/PY this is the formula for that calculation.
there is another problem in there ...
for the first month above mentioned is the formula but from then on  it should be..{(CY-1st month+CY-2nd month)-(PY-1st month+PY-2nd month)}/(PY-1st month+PY-2nd month)... its goes on for every month.
I tried working with running total but it is not working as expected might be I went wrong

It would be a very great if anyone can help me.

Thank you in advance.

[Andrei I]

Are you using a Relational or Dimensional package?
It would be useful if you could create a simplified report with the same issue against a Cognos Samples package

[sepusav]

Hi,
Working with a Relational Package.
That calculation is working is for the first month....
I need help in doing form then on like the moving total....

[Andrei I]

Time Series calculations are so much easier done with Dimensional packages.

Anyway attached is a report example built against Cognos Samples package [GO Data Warehouse (query)]