Matrix Running Total per Month (Example file included)

Hi, StuartSmith 

Try this:

Predicted_Headcount_Measure = COUNTROWS('HR Data') + 0

2022_Total_Laptops = 
Var _start=CALCULATE(SUM('Buffer Stock - Current Stock'[Buffer Stock]))+CALCULATE(COUNTROWS('Full Laptop Table'))

var _Running=CALCULATE(COUNT('HR Data'[Start Date]),FILTER(ALLSELECTED('HR Data'),'HR Data'[Start Date]<Min('HR Data'[Start Date])))
return _start-_Running

2022_Remaining_Laptops = 
Var _start=CALCULATE(SUM('Buffer Stock - Current Stock'[Buffer Stock]))+CALCULATE(COUNTROWS('Full Laptop Table'))

var _Running=CALCULATE(COUNT('HR Data'[Start Date]),FILTER(ALLSELECTED('HR Data'),'HR Data'[Start Date]<=Max('HR Data'[Start Date])))
return _start-_Running

Result:

Please refer to the attachment below for details.

Hope this helps.

Best Regards,
Community Support Team _ Zeon Zheng

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