How to add calcualte column(s) to cross tab report?

[BobaGreek]

Hi forum,

I have cross-tab report that displays products sold in 12 month period by country. So far so good, but now client wants to add another column, that displays last month quantitis. Basically repeat last month column twice. Also they want to see % of (Current_Month)/(12 Months).
I tried to do it several ways and nothing seem to work.

Thank you for your help !