Calculate difference between date group by columns

Hi Juju123 

You can refer to the following solution.

1.Create a num measure to extract the num from operation code.

No =
INT (
    MID (
        SELECTEDVALUE ( Table1[Operation code] ),
        SEARCH ( "E", SELECTEDVALUE ( Table1[Operation code] ),, BLANK () ) + 1,
        LEN ( SELECTEDVALUE ( Table1[Operation code] ) )
            - SEARCH ( "E", SELECTEDVALUE ( Table1[Operation code] ),, BLANK () )
    )
)

2.Create a Rank measure

Rank =
RANKX (
    FILTER (
        ALLSELECTED ( Table1 ),
        [Workflow number]
            IN VALUES ( Table1[Workflow number] )
                && [Article] IN VALUES ( Table1[Article] )
    ),
    [No],
    ,
    ASC
)

3.Then calculate the differnce

Temps entre chaque operation =
VAR a = [Rank] - 1
VAR _predate =
    MAXX (
        FILTER (
            ALLSELECTED ( Table1 ),
            [Workflow number]
                IN VALUES ( Table1[Workflow number] )
                    && [Article]
                        IN VALUES ( Table1[Article] )
                            && [Rank] = a
        ),
        [Operation Date]
    )
RETURN
    IF (
        DATEDIFF ( _predate, MAX ( Table1[Operation Date] ), DAY ) <> BLANK (),
        DATEDIFF ( _predate, MAX ( Table1[Operation Date] ), DAY ),
        0
    )

Output

Best Regards!

Yolo Zhu

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