Year-Over-Year in a Cross-tab

Hi,

There is a requirement for which I need to show Year-Over-Year History for Shipments in a Cross tab. The Cross tab rows should have Current year, Prior Year and Current year -2 along with Materials (innermost row). Calendar months ( Jan - Dec ) on Column. It’s a Power cube reporting. Is there any way to achieve this using dimensional functions without performing union of 3 sub queries…

I tried creating a union of 3 sub queries each of them having slicers for current year, prior year and year-2(relative time categories). But the report performance is very slow

I want to show Current year, Prior year and Current year-2 in a single row and should be dynamically change when we enter into next calendar year(2015)

for example

 [b]Rows                                    columns[/b]       

                       Jan   FEB   MAR    APR  ....  DEC

2014 MaterialA
MaterialB
MaterialC

2013 MaterialA
MaterialB
MaterialC

2012 MaterialA
MaterialB
MaterialC
Can anyone please assist me with this. I have been working on this for a while and couldn’t come up with good results.