Anyone have experience with MDX-Topcount?

[largeselection]

Hello,

So I'm using an Olap connection to create some pivot tables for some reporting. I know how to use the topcount function to create a dynamic set which will show, for example, top 30 salesman by sales volume this year.

Topcount(Salesman, 30, SalesVolume TY)

Then when I use that set in the pivot table it will update based on filters and such in place - so if I put Country as a filter I can see the top 30 salesman by country by salesvolume.

My question - is it possible to see top 30 salesman by largest sales volume increase over last year?

I don't have a variance to LY field in the cube, but I do have SalesVolume this year and SalesVolume last year.

So is it possible to do something like:

Topcount(Salesman, 30, (SalesVolume TY - SalesVolume LY))

??

Any references, insight, help is appreciated