SUM multiple month values over years

Anonymous 

Try:

Aggregation 3 =
IF (
    ISINSCOPE ( 'Date'[Month] ),
    CALCULATE (
        SUMX ( Sales, Sales[Quantity] * Sales[Net Price] ),
        ALLEXCEPT ( 'Date', 'Date'[Month] )
    ),
    SUMX (
        FILTER (
            ALL ( Sales ),
            YEAR ( [Order Date] ) <= SELECTEDVALUE ( 'Date'[Calendar Year Number] )
        ),
        Sales[Quantity] * Sales[Net Price]
    )
)

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Best Regards,

Community Support Team _ Janey