DAX Measure to Average Terminations by Month

Hi, Decal 

Thank you very much for your reply, as well as the sample data provided. Here's the sample data I used:

Here's your DAX expression:

Based on this, I built another DAX expression as shown in the following image:

Terminations =
IF (
    ISINSCOPE ( dimDate[Date].[Year] ),
    [Terminations (Dynamic)],
    SUMX ( ALLSELECTED ( 'dimDate'[Date].[Year] ), [Terminations (Dynamic)] )
)

When I select the corresponding year in the slicer, total updates correctly:

I've provided the PBIX file used this time below.

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If it does not help, please provide more details with your desired output and pbix file without privacy information (or some sample data) .

Best Regards

Jianpeng Li

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