Calculating Moving Range - skipping first data point

[JamesHR]

Hi I am trying to calculate the moving range to make an SPC chart using a measure. However with my calculation I am currently using the moving range includes the first value which I never want to include.

What I want to know is how do I ingore that value when calculating the moving range. 

Moving Range = 
VAR EarlierTime =
    CALCULATE (
        MAX ( 'Data sheet'[Date] ),
        FILTER (
            ALLSELECTED('Data sheet'[Date]),
            'Data sheet'[Date] < SELECTEDVALUE ( 'Data sheet'[Date])
        )
    )
VAR EarlierMeasureValue =
    CALCULATE ( SUM ( 'Data sheet'[Value] ), 'Data sheet'[Date] = EarlierTime)
RETURN
ABS ( EarlierMeasureValue - SUM ( 'Data sheet'[Value] ))

[v-stephen-msft]

Hi @JamesHR ,

You can create a ranking column for your values and then filter out the first value you don't want in your original measure formula.

Power BI RANKX | How to Use RANKX Function

Best Regards,

Stephen Tao

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