Sum Revenue from several months in MDX (1 Viewer)

[noboffinme]

Hi,

I have a Cube file with 24 months of data & one field has Revenue amounts.

I want to nominate 3 consecutive months & add those months Revenue data together.

Rather than use something like [Month].&[201206],[Revenue] + [Month].&[201207],[Revenue] + [Month].&[201208],[Revenue] is there a better way?

Thanks