How to do selective row total in Matrix

Hi NSC7 ,

Please try to create  measure with below dax formula:

$ =
VAR _a =
    SELECTEDVALUE ( 'Table'[Month-Year] )
VAR _b =
    SELECTEDVALUE ( 'Table'[Product] )
VAR _c =
    CALCULATE (
        [ASP],
        FILTER (
            ALL ( 'Table' ),
            [Product] = _b
                && DATEDIFF ( [Month-Year], _a, MONTH ) = 1
        )
    )
VAR _d =
    SELECTEDVALUE ( 'Table'[Unit] )
VAR _e = [ASP]
VAR cur_year =
    YEAR ( TODAY () )
VAR _result =
    IF ( YEAR ( _a ) = cur_year, ( _e - _c ) * _d, BLANK () )
RETURN
    _result

ASP = SELECTEDVALUE('Table'[Rev])*SELECTEDVALUE('Table'[Unit]) 

Measure = IF(ISINSCOPE('Table'[Month-Year]),[$],SUMX('Table',[$]))

Add a matrix visual with fields and measure:

Please refer the attached .pbix file.

Best regards,
Community Support Team_Binbin Yu
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