You must create another aggregated measure using parallel period operator(s) along with some simple numeric operators. Assuming that your existing "Headcount" aggregated measure is calculated as: Distinct [_ByGroup_] ('Row_ID'n) Then your percent difference called "Headcount (% Diff)" would be calculated as: ( ParallelPeriod(_DistinctCount_, 'Row_ID'n, _ApplyAllFilters_, 'Year'n, _Inferred_, _Inferred_, 0, _Full_, {Date}) - ParallelPeriod(_DistinctCount_, 'Row_ID'n, _ApplyAllFilters_, 'Year'n, _Inferred_, _Inferred_, -1, _Full_, {Date}) ) / Abs(ParallelPeriod(_DistinctCount_, 'Row_ID'n, _ApplyAllFilters_, 'Year'n, _Inferred_, _Inferred_, -1, _Full_, {Date})) Set the format of this new aggregated measure to Percent, and drag it into the cross tab. Hope this works for you.
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