FILTER

Hi Syndicate_Admin ,

I suggest you to add a YearMonth column in your data table and then create measures to achieve your goal.

Previous Month Value = 
VAR _PREVIOUS =
    CALCULATE (
        MAX ( 'Table'[YearMonth] ),
        FILTER ( ALL ( 'Table' ), 'Table'[YearMonth] < MAX ( 'Table'[YearMonth] ) )
    )
RETURN
    CALCULATE (
        SUM ( 'Table'[Value] ),
        FILTER ( ALL ( 'Table' ), 'Table'[YearMonth] = _PREVIOUS )
    )

Future Month Value = 
VAR _Future =
    CALCULATE (
        MIN ( 'Table'[YearMonth] ),
        FILTER ( ALL ( 'Table' ), 'Table'[YearMonth] > MAX ( 'Table'[YearMonth] ) )
    )
RETURN
    CALCULATE (
        SUM ( 'Table'[Value] ),
        FILTER ( ALL ( 'Table' ), 'Table'[YearMonth] = _Future )
    )

Result is as below.

Best Regards,
Rico Zhou

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