Hi, Ryan!

Let me show you this via Samples:

This MDX will do the job:

SELECT NON EMPTY {[Measures].[Amount Sold],[MEASURES].[PCT REVENUE SOLD]} ON 0,NON EMPTY HEAD(ORDER([Product].[P1].[Product Category].Members,Measures.[Amount Sold],BDESC),5) ON 1 FROM [HOLEFOODS]

Where PCT REVENUE SOLD has the following expression:

Aggregate(Product.CurrentMember,Measures.[Amount Sold])/Aggregate(Product.CurrentMember.Parent,Measures.[Amount Sold])

This results in Analyzer with the following pivot:

It shows top 5 Product categories by revenue with percent to Total.

Hope this helps