Yes, i thought the same and i have implemented that with Date only..but the problem is with Members ...The member selection of Date is dynamic here so i have added the .Parent.chidlren to that but it wasnt helping

[Date].[Calendar].[Date].[Dynamic Member Selection].Parent.children.

Heres where i got struck when i have implemented the above expression ..anyway what you have provided is correct but i need to check here how can i achieve this by dynamic selection of Date memebers