Calculating average of date difference between specific rows

[GertRiet]

Hello everyone!

I am having trouble in creating a specific logic.
The ideia is find the average of the diference of the days between specific rows.

For example:
IDDateCriteria

1	18/01/2018	First
2	25/01/2018	First
3	21/01/2018	First
4	01/02/2018	First
1	03/02/2018	Second
2	14/03/2018	Second
1	05/02/2018	Third

In this example, I want to know the date difference between criteria but in the same ID.
The formula is = DateDifference ID = Second - First
In excel that would be:
ID 1 = 03/02/2018-18/01/2018 = 16 days
ID 2 = 14/03/2018-25/01/2018 = 48 days
ID 3 = Blank (there is no second criteria)
ID 4 = Blank (there is no second criteria)
So, the average of that is 32.

Just like the table under:

DateDIFF (Second - First)
ID 1	16,00
ID 2	48,00
ID 3	Blank
ID 4	Blank
Average	32,00

I want to do the same for (Third-Second), and so on...

How Can I create a Measure of that?


Thanks ikn advance, I am stuck in this problem for a few days now....

PS: I want create that in DAX not in Power Query.

[v-cherch-msft · Accepted solution]

Hi @GertRiet

You may try to create measures as below:

Diff =
VAR a =
    CALCULATE (
        MAX ( Table1[Date] ),
        FILTER (
            ALL ( Table1 ),
            Table1[Date] < MAX ( Table1[Date] )
                && Table1[ID] = MAX ( Table1[ID] )
        )
    )
RETURN
    DATEDIFF ( a, MAX ( Table1[Date] ), DAY )

Average =
AVERAGEX (Table1, [Diff] )

Regards,

Cherie