12-month rolling calculation with two moving time variables

Hi SebL ,

You need a calendar table and use the calendar table to create relationships with 'Costs Table' and 'Days Paid Table'.

Calendar table:

Relationships:

Then please create these measures:

Sum of NbDays = 
IF (
    ISINSCOPE ( 'Calendar'[Quarter] ) || ISINSCOPE ( 'Calendar'[Month] ),
    CALCULATE (
        SUM ( 'DaysPaidTable'[NbDays] ),
        'DaysPaidTable'[ReferenceNumber] = MAX ( 'DaysPaidTable'[ReferenceNumber] )
    )
)

12-month rolling costs = 
VAR _start = MAX('Calendar'[Year])*100+MIN('Calendar'[MonthNum])
VAR _end = _start+100
VAR _result =
IF (
    [Sum of NbDays] >= 180,
    CALCULATE (
        SUM ( 'CostTable'[Amount] ),
        FILTER (
            ALL('Calendar'),
            'Calendar'[Year-Month]>=_start&&'Calendar'[Year-Month]<=_end          
        )
    )
)
RETURN
_result

Test result:

The PBIX file is attached for reference.

Best Regards,
Gao
Community Support Team

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