Merge Table by itself

Hi, Anonymous 

Based on your description, I created data to reproduce your scenario. The pbix file is attacehd in the end.

Table:

You may create a calculated column as below.

Result = 
var _lastvalue = 
CALCULATE(
    SUM('Table'[Total]),
    FILTER(
        'Table',
        'Table'[AccNum]=EARLIER('Table'[AccNum])&&
        'Table'[Date]=EARLIER('Table'[PreviousDate])
    )
)
return
COALESCE(_lastvalue,0)

Result:

Or you can create a calculated table as below.

NewTable = 
ADDCOLUMNS(
    'Table',
    "Result2",
    var _lastvalue = 
    CALCULATE(
        SUM('Table'[Total]),
        FILTER(
            'Table',
            'Table'[AccNum]=EARLIER('Table'[AccNum])&&
            'Table'[Date]=EARLIER('Table'[PreviousDate])
        )
    )
    return
    COALESCE(_lastvalue,0)
)

Result:

Best Regards

Allan

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