Datediff with multiple criteria

Hi reddevil ,

Based on the information, try using the following DAX formula.

Total Overdue Count update = 
VAR StartDate = MAX(Test[Last Test Date])
VAR EndDate = TODAY()
VAR Frequency = MAX(Test[Test Frequency])
VAR MonthDiff = DATEDIFF(StartDate, EndDate, MONTH)
VAR OverdueThreshold =
    SWITCH(
        TRUE(),
        Frequency = "Annually", 12,
        Frequency = "Biennial", 24,
        Frequency = "Six Monthly", 6,
        Frequency = "Quarterly", 3,
        Frequency = "Every 18 Months", 18,
        BLANK()
    )
RETURN
    IF(
        NOT(ISBLANK( OverdueThreshold)) &&
        MonthDiff >= OverdueThreshold,
        DISTINCTCOUNT(Test[ID]),
        0
    )

Also, the example data you provided does not have the Test[ID] column and Test[Status Name] column in it.

Best Regards,

Wisdom Wu

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