MDX RANK Calulated Measure has 1 for every row - mdx

Question

I'm trying to create a calculated measure in an MDX query that gets the rank for a dimension ordered by a measure. The problem is that for each row all I get is 1 or, the count of the dimension if I change the sort order.
Here is my measure
MEMBER [Measures].[Approved wk to wk Rank] AS RANK (
[FRR Group Matrix].[Group Name].CurrentMember,
ORDER(
[FRR Group Matrix].[Group Name].[Group Name].ALLMEMBERS, [Measures].[Approved wk to wk %], BDESC
),
[Measures].[Approved wk to wk %]
)
My measures are in my columns, and my dimensions in rows. Here is where I define my rows, and where I believe I have the problem:
{ ([FRR Group Matrix].[Group Name].[Group Name].ALLMEMBERS
* [FRR Group Matrix].[FRRCode].[FRRCode].ALLMEMBERS ) } ON ROWS
If I change to the following I will get a good rank, but I still want to keep both columns
{ [FRR Group Matrix].[Group Name].[Group Name].ALLMEMBERS } ON ROWS
So how can I get my rank to work with both tuples?

Answer 1

Put the whole tuple in the RANK and ORDER. NONEMPTY may not be necessary for your specific problem, but it will exclude blanks from your ranking, and probably speed up the execution time.
SET [X] AS
ORDER(
NONEMPTY(
[FRR Group Matrix].[Group Name].[Group Name]
*
[FRR Group Matrix].[FRRCode].[FRRCode],
[Measures].[Approved wk to wk %]
),
[Measures].[Approved wk to wk %],
BDESC
)
MEMBER [Measures].[Approved wk to wk Rank] AS
RANK (
(
[FRR Group Matrix].[Group Name].CurrentMember,
[FRR Group Matrix].[FRRCode].CurrentMember
),
[X],
[Measures].[Approved wk to wk %]
)