Summarize a summarized table

Hi Cado_one,

You can try to use the following measure formulas if helps:

Formula =
VAR t1 =
    SUMMARIZE ( Source, [LOCATIONS], [MONTH], "SumMonths", SUM ( Source[Values] ) )
VAR t2 =
    SUMMARIZE (
        Source,
        [LOCATIONS],
        "AverageLocations",
            AVERAGEX (
                FILTER ( t1, [LOCATIONS] = EARLIER ( Source[LOCATIONS] ) ),
                [SumMonths]
            )
    )
RETURN
    IF (
        ISINSCOPE ( Dates[Month] ),
        SUM ( Source[Values] ),
        IF (
            ISINSCOPE ( Source[LOCATIONS] ),
            AVERAGEX ( t1, [SumMonths] ),
            AVERAGEX ( t2, [AverageLocations] )
        )
    )

If the above formula also doesn't help, please share more detailed information to help us clarify your scenario to test.

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Regards,

Xiaoxin Sheng