I'm having a problem with a calculated measure that gets a distinct count of [measure].[email] on COLUMN against [occupations].members on ROW with 26 kinds of occupations. However the MDX below outputs 27 on All Occupations row, and 26 on each of the occupations rows.

Count(CrossJoin( {[Email]}, Descendants([Occupation].CurrentMember, [Occupation].[Occupation])), ExcludeEmpty)

Why does the query above count the # of occupations instead of the # of emails?

please advice.. thanks!