Variables Exits

I'm trying to design a dynamic query that looks like this:

20005 -- Jan06 --- Feb06 --- Mar06 --- Apr06 ... Dec06 --- YTD

My Problem, ich you give per e.g Dezember, all Months have to appear. Or you give may, your going to receive till may.

In the year to date column, i muss do a calculation.

Do you have some Ideas?

Cheers