DAX Calculation: Average Cumulative Spend by 'Days Since'

Hi @

Because not clear about how your data model and table structure look like, so I create a sample.

You can take steps bellow for reference.

-

1. create a column

DaysSinceMembershipBegan column =
VAR _start =
    RELATED ( Membership[MembershipStart] )
RETURN
    DATEDIFF ( _start, ( Orders[Date] ), DAY )

2. create the measure:

if you want to divide by actual number,

then create the measure:

_average =
VAR filter_table =
    FILTER (
        ALL ( Orders ),
        Orders[DaysSinceMembershipBegan column]
            <= SELECTEDVALUE ( Orders[DaysSinceMembershipBegan column] )
    )
VAR total =
    CALCULATE ( SUM ( Orders[Value] ), filter_table )
VAR membercount =
    CALCULATE ( DISTINCTCOUNT ( Orders[MembershipNo] ), filter_table )
VAR _div =
    DIVIDE ( total, membercount )
RETURN
    _div

Result:

OR

if you want to divide by total number in membership table, create this measure

_average1 =
VAR filter_table =
    FILTER (
        ALL ( Orders ),
        Orders[DaysSinceMembershipBegan column]
            <= SELECTEDVALUE ( Orders[DaysSinceMembershipBegan column] )
    )
VAR total =
    CALCULATE ( SUM ( Orders[Value] ), filter_table )
VAR membercount =
    COUNTROWS ( Membership )
VAR _div =
    DIVIDE ( total, membercount )
RETURN
    _div

result:

 Hope this helps.

Best Regards,

Community Support Team _ Tang

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