Dynamic Average (calendar year to date)

Hi, Anonymous 

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

Table:

You may create  calculated columns and a measure as below to get the average of Sales from January2020 until the latest month(August) that year.
Calculated column:

Year = YEAR('Table'[Date])

Month = MONTH('Table'[Date])

YearMonth = YEAR('Table'[Date])*100+MONTH('Table'[Date])

Measure:

Avg = 
DIVIDE(
    CALCULATE(
        SUM('Table'[Sell Out(MSU)]),
        FILTER(
            ALL('Table'),
            [Year]=YEAR(TODAY())&&
            [Month]>=1&&
            [Month]<=MONTH(TODAY())
        )
    ),
    CALCULATE(
        DISTINCTCOUNT('Table'[YearMonth]),
        FILTER(
            ALL('Table'),
            [Year]=YEAR(TODAY())&&
            [Month]>=1&&
            [Month]<=MONTH(TODAY())
        )
    )
)

Result:

Best Regards

Allan

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