Average Days

Hi JB17 ,

According to your description, here are my steps you can follow as a solution.

(1) This is my test data. 

(2) We can create  measures. 

ProcessingDaysDifference = 
VAR CurrentDate = MAX('Table'[Processing Date])
VAR PreviousDate =
    CALCULATE(
        MAX('Table'[Processing Date]),
        FILTER(
            ALL('Table'),
            'Table'[system ID]=MAX('Table'[system ID]) &&
            'Table'[Processing Date] < CurrentDate
        )
    )
RETURN
DATEDIFF(PreviousDate, CurrentDate, DAY)

AverageDaysPerMonth = 
var _min=CALCULATE(MIN('Table'[Processing Date]),FILTER(ALL('Table'),'Table'[system ID]=MAX('Table'[system ID]) && YEAR('Table'[Processing Date])=YEAR(MAX('Table'[Processing Date])) && MONTH('Table'[Processing Date])=MONTH(MAX('Table'[Processing Date]))))
var _max=CALCULATE(MAX('Table'[Processing Date]),FILTER(ALL('Table'),'Table'[system ID]=MAX('Table'[system ID]) && YEAR('Table'[Processing Date])=YEAR(MAX('Table'[Processing Date])) && MONTH('Table'[Processing Date])=MONTH(MAX('Table'[Processing Date]))))
var _day=IF( DATEDIFF(_min, _max, DAY)=0,1,DATEDIFF(_min, _max, DAY))
var _count=COUNTROWS(FILTER(ALL('Table'),'Table'[system ID]=MAX('Table'[system ID]) && YEAR('Table'[Processing Date])=YEAR(MAX('Table'[Processing Date])) && MONTH('Table'[Processing Date])=MONTH(MAX('Table'[Processing Date]))))
return DIVIDE(_day,_count,0)

(3) Then the result is as follows.

If the above one can't help you get the desired result, please provide some sample data in your tables (exclude sensitive data) with Text format and your expected result with backend logic and special examples. It is better if you can share a simplified pbix file. Thank you.

Best Regards,

Neeko Tang

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