Average Between Three Dates Versus Main Date

Hi Anonymous 

Maybe you can try this:
I added some date into the sample data to test:

Then add 3 calculate columns to get the Datediff of the 3 type date,like this:

Then i create a table:

And a measure:

Lag1 = 
VAR _aveValue = SELECTEDVALUE('Table'[Value])
	VAR result = SWITCH(
		_aveValue,
		"ave_sDate", CALCULATE(
			SUM('Table (2)'[SDATE]) / COUNTROWS('Table (2)'),
			FILTER(
				ALLSELECTED('Table (2)'),
				'Table (2)'[Submission Date] <> BLANK()
			)
		),
//Get the average of the sum of the datediff from physical date to submission Date
		"ave_paDate", CALCULATE(
			SUM('Table (2)'[PADATE]) / COUNTROWS('Table (2)'),
			FILTER(
				ALLSELECTED('Table (2)'),
				'Table (2)'[Price Approved Date] <> BLANK()
			)
		),
		"ave_taDate", CALCULATE(
			SUM('Table (2)'[TADATE]) / COUNTROWS('Table (2)'),
			FILTER(
				ALLSELECTED('Table (2)'),
				'Table (2)'[Terms Approved Date] <> BLANK()
			)
		)
	)
	RETURN
		result

The result is as follow:

Best Regards,

Zhengdong Xu

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