LISTING 1: MDX Expression to Create a Calculated Member

With Member [Measures].[Unique Customers] 
AS 'Count( {[Unit Sales]} * Descendants( 
[Customers].CurrentMember, [Customers].[Name] ), ExcludeEmpty )'
SELECT { [Unique Customers] } ON COLUMNS,
  TopCount( Descendants([Product].[All Products].
[Drink].[Alcoholic Beverages].[Beer and Wine].[Beer],
[Product].[Product Name]), 5, [Unique Customers] ) ON ROWS
FROM Sales
WHERE ([Customers].[All Customers].[USA].[CA])