How to Categorize Dates based on Relative Date Slicer

Hi Bjar2023 ,

Please have a try.

Create a table.

Period = {"Same Period last year","Selected Period"}

Then create a measure.

PeriodValue =
VAR _a =
    ALLSELECTED ( 'Date'[Date] )
VAR _b =
    SELECTCOLUMNS ( _a, "Last Year", EDATE ( [Date], -12 ) )
RETURN
    SUMX (
        'Period',
        SWITCH (
            [Period],
            "Selected Period", SUMX ( FILTER ( 'Table', [date] IN _a ), [value] ),
            "Same Period last year", SUMX ( FILTER ( 'Table', [date] IN _b ), [value] )
        )
    )

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