GET.PREVIOUS
This function returns the name of the element which, in the hierarchy, is previous to, and at the same level as, an element which you specify.
Syntax
=MDX.GET(Database Alias, Cube, "Element Unique Name"&".PrevMember.name")
Arguments to this function can be strings, or references to cells containing strings. If strings, they must be enclosed in quotes.
Example
This example returns 'Car Tires All Season':
=MDX.GET("Best Practices OLAP", "ANALYSIS", "[PRODUCT].[All Tires].[Car Tires Summer]"&".PrevMember.name")