Rolling 12month sum

Hi StevenCollins ,

According to your description, you want to calculate sum value of the rolling 12 months based on the date you selected in the slicer, but the formula only take the selected month into calculation, you should use the removefilters

function in the formula. 

I create a sample.

Modify the measure formula like this:

Measure =
CALCULATE (
    SUM ( Combined[Sales History (Value)] ),
    DATESINPERIOD ( 'Combined'[Date], MAX ( Combined[Date] ), -12, MONTH ),
    REMOVEFILTERS ( Combined[Report Month] )
)

Use the Report Month column in the slicer and get the correct result.

I attach my sample below for your reference.

Best Regards,
Community Support Team _ kalyj

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