Ok thanks for all the details now one simple query.
If user enters the month 08.2013 what output are they expecting ?
For the month data ----YTD of that month - YTD of previous month correct.
This will be calculated based on user input..Please confirm.
I think with two selections and one formula it should happen.
Restrict the keyfigure--with the calmonth ----user input variable
Second selection same----offset of -1 to get previous month YTD
Formula---Selection 1 - selection 2
So based on user input it will work--If user enters 08.2013
So first selection will hold that value and the second of previous month
And finally the subtraction of both.
I hope this is what you are looking for.
Regards,
AL