DAX Measure to calculate % of tickets closed within TAT

 %TICKETS_CLOSED_WITHIN_TAT(%Success) =

VAR FilteredTable =

    FILTER(

        'Closed,Rejected',

        'Closed,Rejected'[TAT_Closed_Req] = "Within TAT" //[TAT_Closed_Req] Is a measure

    )

RETURN

DIVIDE(

    CALCULATE(COUNT('Closed,Rejected'[Id]), FilteredTable),

    CALCULATE(COUNT('Closed,Rejected'[Id]))

)