Help with DAX formula

Hi, rit_ty7 

Based on your information, I create a sample table:

Then create a new measure and try the following DAX:

Hit_Rate%_15th_Monthly = 
CALCULATE(
    DIVIDE(
        COUNTROWS(FILTER('Table', 'Table'[Hit by 15th] = 1)), 
        COUNTROWS('Table'), 
        0
    ),
    ALLEXCEPT('Table', 'Table'[Month])
)

Create a slicer visual, put Month in slicer visual. Here is my preview:

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Best Regards

Yongkang Hua

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