Average payment for previous month

I downloaded and looked at your file.  Only change I see to make is to remove the ".Date" part.  Try this:

Avg_PreviousMonth_payment =
CALCULATE (
    AVERAGE ( DataFromDB[Payment_Amt] ),
    PREVIOUSMONTH ( CalendarTable[Date] )
)

JulietZhu

One way to reduce is:

Creating a calculated column in your calendar table

DaysinMonth =
DATEDIFF (
    STARTOFMONTH ( CalendarTable[Date] );
    ENDOFMONTH ( CalendarTable[Date] );
    DAY
)
    + 1

And in the measure:

TotalPayment_PreviousMonth =
VAR DaysinPrevMonth =
    CALCULATE (
        SELECTEDVALUE ( CalendarTable[DaysinMonth] );
        PREVIOUSMONTH ( CalendarTable[Date] )
    )
RETURN
    DIVIDE (
        CALCULATE (
            SUM ( DataFromDB[Payment_Amt] );
            PREVIOUSMONTH ( CalendarTable[Date] )
        );
        DaysinPrevMonth
    )

Regards

Victor

Lima - Peru