Incorrect sort for Year/Period

Hi,

In my OLAP report I am trying to sort year period field but it is giving wrong output.

Please check below snaps to understand it more.

I had made Year/Period filed Display as key and am trying to sort it in ascending order but unable to sort it. But at backend in BEx I am able to sort it in correct way.

I’m not sure we can create a variable, in OLAP, to strip some characters and get aresult with only MM.YYYY(001.2013).

Regards,

Mithun