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TimmK's avatar
TimmK
Icon for Helper IV rankHelper IV
3 years ago
Solved

How to Dynamically Subtract Variable Days?

For simplicity I have a table with the three columns "Order Key", "Date" and "Days".   I would like to use a DAX measure (or if this is not possible a calculated column) to subtract the days from t...
  • johnt75's avatar
    johnt75
    3 years ago

    You could create a measure like

    Adjusted date =
VAR ReferenceDate =
    SELECTEDVALUE ( 'Table'[Date] )
VAR ReferenceDays =
    SELECTEDVALUE ( 'Table'[Days] )
VAR BaseDate = ReferenceDate - ReferenceDays
VAR Result =
    SWITCH ( WEEKDAY ( BaseDate ), 1, BaseDate - 2, 7, BaseDate - 1, BaseDate )
RETURN
    Result
johnt75's avatar
johnt75
Icon for Super User rankSuper User
3 years ago

You could create a measure like

Adjusted date =
VAR ReferenceDate =
    SELECTEDVALUE ( 'Table'[Date] )
VAR ReferenceDays =
    SELECTEDVALUE ( 'Table'[Days] )
VAR BaseDate = ReferenceDate - ReferenceDays
VAR Result =
    SWITCH ( WEEKDAY ( BaseDate ), 1, BaseDate - 2, 7, BaseDate - 1, BaseDate )
RETURN
    Result
  • TimmK's avatar
    TimmK
    Icon for Helper IV rankHelper IV
    3 years ago

    johnt75 Ah, actually the last part unfortunately does not work as intended. For example, let us say the reference date is November 21, 2022 (Monday) and 3 days should be subtracted. Then based on your measure the result would be November 18, 2022 (Friday). However, it actually should be November 16, 2022 (Wednesday) because it should be 3 workdays earlier, which means November 21, 2022 - 2 weekend days - 3 workdays.

     

    Could you please help with a solution?

    • johnt75's avatar
      johnt75
      Icon for Super User rankSuper User
      3 years ago

      Try

      Adjusted date =
VAR ReferenceDate =
    SELECTEDVALUE ( 'Table'[Date] )
VAR ReferenceDays =
    SELECTEDVALUE ( 'Table'[Days] )
VAR BaseDate = ReferenceDate - ReferenceDays
VAR WorkingDaysDiff =
    NETWORKDAYS ( BaseDate, ReferenceDate )
VAR Result = BaseDate - ( ReferenceDays - WorkingDaysDiff )
RETURN
    Result
      • TimmK's avatar
        TimmK
        Icon for Helper IV rankHelper IV
        3 years ago

        This is what I get with the updated measure:

         

        Almost there. If the date is 2022-11-16 (WED) and 2 days should be subtracted then the result should be 2022-11-14 (MON) instead of 2022-11-15 (TUE). It seems that addtional 1 day needs to be subtracted for each row.

         

        Also, for example if the date is 2022-11-16 (WED) and 3 days should be subtracted then the result should be 2022-11-11 (FRI) instead of 2022-11-13 (SUN).

         

        Additional question: How can I remove the 30.12.1899 from the total?

         

        Thank you very much for your great help.