creating a monthly average column

Hi JaviGoldstein ,

Please try to create a new column with below dax formula:

Column =
VAR cur_combo = [Combo]
VAR cur_date = [Date]
VAR cur_year =
    YEAR ( cur_date )
VAR cur_month =
    MONTH ( cur_date )
VAR tmp =
    FILTER (
        'Table',
        [Combo] = cur_combo
            && YEAR ( [Date] ) = cur_year
            && MONTH ( [Date] ) = cur_month
    )
RETURN
    AVERAGEX ( tmp, [Rate] )

Please refer the attached .pbix file.

Best regards,
Community Support Team_Binbin Yu
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