Aggregate measures for calculation groups + allow as implicit measures

Calculation groups are interesting, but have two show-stopping limitations

• discouraging implicit measures, and hiding them from the editor.
• Applying to all measures in a visual when selected - rather than specific ones.

In order to use calculation groups powerfully per-column, every field on which a calculation group item or aggregate function can be used needs a measure adding the calculation as a filter.

If you have say 200 measures and 16 calculation perspectives for different date grregations, plus the usual count sum avg min max etc ... that's an awful lot of measues that are simply aggregation wrappers to maintain.

It would be powerful to be able to create reusable aggregation calculations in the semantic model that can be selected as an implicit measure.

e.g.

I want to allow report designers to show all of the fields both as a regular sum and a last year sum.

I define a new aggregate calculation

∑LY =CALCULATE(SUM(SELECTEDCOLUMN()), SAMEPERIODLASTYEAR(Dates[Date]))

And then be able to choose ∑LY as an implicit aggregation in the field well.

The field itself becomes the SELECTEDCOLUMN() in the calculation group.

These could also be callable from DAX measures

e.g.

∑LY Value $ = APPLY([∑LY], [$ Value])

Oh ... this all boils down to functions, doesn't it?!

Functions would simplify so much, and save having strange paradigms like calculation groups as filters whose main motivation seem to be to avoid adding functions.