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andy291086
Frequent Visitor

DAX Logic for Calculating Rolling Sum

Hi Team, 

 

I am new to Power BI and DAX. I had been assigned to convert an Excel report into Power BI which has the following calculations. 

andy291086_3-1701067108832.png

 

I am stuck up with the calculations for Behind , which is based on the excel formula , Prior Behind Days + ( Target Days - Rolling Average Days) / Weeks left. Behind Days for Week 1 is 0 . 

 

For .e,g, for Week 3, the behind is calculated as 0.5 + (350 - 295.67)/49 = 1.6, 

 

Can you please help ?

 

Cheers, 

Andy

 

 

1 ACCEPTED SOLUTION
Anonymous
Not applicable

Hi @andy291086 ,

I created a sample pbix file(see the attachment) for you, please check if that is what you want.

Week Number = VALUE(RIGHT('Table'[Week], LEN('Table'[Week]) - 5))
Column = 
VAR _preweek =
    CALCULATE (
        MAX ( 'Table'[Week Number] ),
        FILTER ( 'Table', 'Table'[Week Number] < EARLIER ( 'Table'[Week Number] ) )
    )
VAR _prewbdays =
    CALCULATE (
        MAX ( 'Table'[Behind Days] ),
        FILTER ( 'Table', 'Table'[Week Number] = _preweek )
    )
RETURN
    _prewbdays + ( 'Table'[Target Days] - [Rolling Average - Days] ) / 'Table'[Weeks Left]

vyiruanmsft_0-1701238156100.png

Best Regards

View solution in original post

1 REPLY 1
Anonymous
Not applicable

Hi @andy291086 ,

I created a sample pbix file(see the attachment) for you, please check if that is what you want.

Week Number = VALUE(RIGHT('Table'[Week], LEN('Table'[Week]) - 5))
Column = 
VAR _preweek =
    CALCULATE (
        MAX ( 'Table'[Week Number] ),
        FILTER ( 'Table', 'Table'[Week Number] < EARLIER ( 'Table'[Week Number] ) )
    )
VAR _prewbdays =
    CALCULATE (
        MAX ( 'Table'[Behind Days] ),
        FILTER ( 'Table', 'Table'[Week Number] = _preweek )
    )
RETURN
    _prewbdays + ( 'Table'[Target Days] - [Rolling Average - Days] ) / 'Table'[Weeks Left]

vyiruanmsft_0-1701238156100.png

Best Regards

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