First Week of Month to Include Days from Previous Month

Hi dwelsh 

You can refer to the following sample data.

Sample data 

1.I create a calendar table and create a relationship among the table.

2.Create a measure.

MEASURE =
VAR a =
    DATE ( MAX ( 'Calendar'[Year] ), MONTH ( MAX ( 'Calendar'[Date] ) ), 1 )
VAR b =
    a - WEEKDAY ( a, 2 ) + 1
VAR c =
    a + 7
        - WEEKDAY ( a, 2 )
RETURN
    CALCULATE ( SUM ( 'Table'[Value] ), DATESBETWEEN ( 'Calendar'[Date], b, c ) )

3.Put the following field to the matrix visual. the date column is belong to the data table not the calendar table.

Output

Best Regards!

Yolo Zhu

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