Forecasting based on current month (With Total Sales)

Hi, andrewb95 

Based on your description, I created data to reproduce your scenario. The pbix file is attached in the end.

Table:

You may create two measures as below.

TotalSalesMonth To Date = 
CALCULATE(
    SUM('Table'[Value]),
    FILTER(
        ALL('Table'),
        [Date]<=MAX('Table'[Date])&&
        FORMAT([Date],"mmm yyyy")=FORMAT(MAX('Table'[Date]),"mmm yyyy")
    )
)

Forecast TotalSalesMonth = 
var _days = DAY(EOMONTH(MAX('Table'[Date]),0))
var _avg = 
CALCULATE(
    AVERAGE('Table'[Value]),
    FILTER(
        ALL('Table'),
        'Table'[Date]<=MAX('Table'[Date])&&
        FORMAT([Date],"mmm yyyy")=FORMAT(MAX('Table'[Date]),"mmm yyyy")
    )
)
return
_avg*_days

Result:

Best Regards

Allan

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