MDX query to show year level data for all years except the last one, and month level data for the last year, in SSAS

Answer 1

SELECT {NULL:ClosingPeriod([Date].[Calendar].[Calendar Year], [Date].[Calendar].DefaultMember).PrevMember, DESCENDANTS(ClosingPeriod([Date].[Calendar].[Calendar Year], [Date].[Calendar].DefaultMember), [Date].[Calendar].[Month]) } ON 0
FROM [Sales Summary];