DAX Measure Average Count over Time

Hi azs 

Due to I don't know your data model, I build a sample to have a test.

Here I have two open days 2021/05/20 and 2021/05/24.

2021/05/20 Part:

2021/05/20: opened A;B;C;D --> overdue count 0

2021/05/21: C is due to and closed as well; A&B&D are due to but not finished yet --> overdue count 3

2021/05/22: A&B are overdue but closed; D is overdue but not closed --> overdue count 1

2021/05/23: D is overdue but closed --> overdue count 0

So the Averge count is (0+3+1+0)/ 4 = 1

2021/05/20 Part is the same like yours.

Measures:

Diff Day = DATEDIFF(MAX('Table'[Due to]),MAX('Table'[Close]),DAY)

Avg = 
VAR _Overdue = SUMX('Table',[Diff Day])
VAR _AllDaycount = DATEDIFF(MAX('Table'[Open]),MAX('Table'[Close]),DAY) +1
VAR _Avg = DIVIDE(_Overdue,_AllDaycount)
Return
_Avg

Result is as below.

Best Regards,

Rico Zhou

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