Calculation on headcount and leavers_moving average

Hi anony711 ,

First we need a calendar table like:

relationships:

Please try:

Measure = 
VAR _min_date = MIN('Calendar'[Date])
VAR _max_date = EDATE(_min_date,12)
VAR _start_monthyear = MAX('Calendar'[MonthYear])
VAR _end_monthyear = CALCULATE(MAX('Calendar'[MonthYear]),FILTER(ALL('Calendar'),'Calendar'[Date]=_max_date-1))
VAR _leavers = CALCULATE(SUM('Table3'[Number of leavers]),FILTER(ALL('Calendar'),'Calendar'[Date]>=_min_date&&'Calendar'[Date]<_max_date))
VAR _number_of_employees_at_the_start = CALCULATE(MAX('Table1'[Starting headcount]),'Calendar'[Date] = _min_date)
VAR _max_date_2 = CALCULATE(MAX('Table2'[Date]),FILTER(ALL('Table2'),'Table2'[Date]<_max_date))
VAR _number_of_employees_at_the_end = CALCULATE(MAX('Table2'[Ending headcount]),'Calendar'[Date] = _max_date_2)
VAR _result = DIVIDE(_leavers,(_number_of_employees_at_the_start+_number_of_employees_at_the_end)/2)
RETURN
_result

Best Regards,
Gao
Community Support Team

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