Dynamic difference between dates present in a single column based on slicer selection

Hi ALobo94 

You can refer to the following solution.

1.It is better that unpivot the column to the following format in power query.

2.Create the following measures.

theDateDifference =
VAR _maxdate =
    CALCULATE (
        MAX ( 'Table'[Value] ),
        ALLSELECTED ( 'Table' ),
        'Table'[Tax Invoice] IN VALUES ( 'Table'[Tax Invoice] ),
        'Table'[Stage] IN VALUES ( 'Table'[Stage] )
    )
VAR _mindate =
    CALCULATE (
        MIN ( 'Table'[Value] ),
        ALLSELECTED ( 'Table' ),
        'Table'[Tax Invoice] IN VALUES ( 'Table'[Tax Invoice] ),
        'Table'[Stage] IN VALUES ( 'Table'[Stage] )
    )
RETURN
    DATEDIFF ( _mindate, _maxdate, DAY )

Date Difference = AVERAGEX(VALUES('Table'[Tax Invoice]),[theDateDifference])

Then put the date difference measure to the visual.

Output

Best Regards!

Yolo Zhu

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