How to select data from another table with a single slicer

Hi ddimitrov ,

According to your description, here's my solution. Create two measures.

MdaysTarget =
IF (
    ISFILTERED ( Actuals[Program] ),
    SUMX (
        FILTER (
            ALL ( 'Targets' ),
            'Targets'[Quarter] = SELECTEDVALUE ( Actuals[Quarter] )
                && 'Targets'[Program] = SELECTEDVALUE ( 'Actuals'[Program] )
        ),
        'Targets'[Mdays]
    ),
    IF (
        ISFILTERED ( 'Actuals'[Quarter] ),
        SUMX (
            FILTER (
                ALL ( 'Targets' ),
                'Targets'[Quarter] = SELECTEDVALUE ( Actuals[Quarter] )
            ),
            'Targets'[Mdays]
        ),
        SUM ( 'Targets'[Mdays] )
    )
)

Difference =
'Actuals'[MdaysTarget] - SUM ( 'Actuals'[ Mdays] )

Get the result.

I attach the file below for your reference.

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Best regards,

Community Support Team_yanjiang