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Tonocop2390's avatar
Tonocop2390
New Member
1 year ago
Solved

How to create a column that completes itself based on values from the column itself?

For example I have a table that has actuals from January to April, and then for the rest of the year, I have to calculate based on the previous value.

Let's say April has 1000, so for May my calculation should be April's value + 500.  Then for June, I need to take May's value and add 500 and so on.  

Is this possible to do in DAX?  Is using the same values calculated in a column to complete the rest, self referencing.

Thanks for the help.

 

  • Anonymous's avatar
    Anonymous
    1 year ago

    Hi Tonocop2390 ,

    Please try the code below.

     

    Column2 = 
Var _Month=
CALCULATE(
    MAX('Table'[Month]),
    FILTER('Table',[Value]<>BLANK())
    )
Var _Sum=
CALCULATE(
    SUM('Table'[Column]),
    FILTER('Table',[Month]<=EARLIER('Table'[Month])&&[Month]>=_Month)
    )
RETURN
IF([Value]<>BLANK(),[Value],_Sum)

     

     

    Best regards,

    Lucy Chen

    If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

     

3 Replies

  • lbendlin's avatar
    lbendlin
    Icon for Super User rankSuper User
    1 year ago

    You cannot do self referencing in DAX.  You can do aggregations like SUMX in some scenarios.

     

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  • Anonymous's avatar
    Anonymous
    Not applicable
    1 year ago

    Hi Tonocop2390 ,

    Please try the code below.

     

    Column2 = 
Var _Month=
CALCULATE(
    MAX('Table'[Month]),
    FILTER('Table',[Value]<>BLANK())
    )
Var _Sum=
CALCULATE(
    SUM('Table'[Column]),
    FILTER('Table',[Month]<=EARLIER('Table'[Month])&&[Month]>=_Month)
    )
RETURN
IF([Value]<>BLANK(),[Value],_Sum)

     

     

    Best regards,

    Lucy Chen

    If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

     

  • Poojara_D12's avatar
    Poojara_D12
    Icon for Super User rankSuper User
    1 year ago

    Hi Tonocop2390 

    Yes, you can achieve this in DAX by creating a calculated column using a pattern that references previous rows. However, DAX doesn't allow true self-referencing in calculated columns directly. Instead, we use functions like EARLIER or VAR along with row context to simulate this behavior.

     

    Create a Calculated Column

    DAX:

     

    Calculated Column =
VAR CurrentMonth = Table[Month]
VAR PreviousMonthValue =
    CALCULATE(
        MAX(Table[Calculated Column]),
        FILTER(
            Table,
            Table[Month] = FORMAT(DATEADD(DATEVALUE("1 " & CurrentMonth), -1, MONTH), "mmmm")
        )
    )
RETURN
IF(
    ISBLANK(Table[Actuals]),
    PreviousMonthValue + 500,
    Table[Actuals]
)

     

     

    Also, 

    If your table isn't sorted by months, ensure to use a date field or sort it correctly for accurate calculations.

    DAX calculated columns are evaluated row by row, so they cannot dynamically reference themselves. The FILTER and CALCULATE pattern simulates this behavior.

     

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    Kind Regards,
    Poojara
    Data Analyst | MSBI Developer | Power BI Consultant
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