Calculate difference between current and previous row with a condition

Hi Sultanista ,

You can try this method:

New column:

Diff =
VAR _curr =
    CALCULATE (
        SUM ( 'Table'[Applicants] ),
        'Table'[Agregation Type] = "All Branches - YTD"
    )
RETURN
    IF (
        [Fiscal Month] = 1
            || 'Table'[Agregation Type] <> "All Branches - YTD"
            || ISBLANK ( 'Table'[Applicants] ),
        BLANK (),
        _curr
            - CALCULATE (
                SUM ( 'Table'[Applicants] ),
                FILTER (
                    'Table',
                    [Agregation Type] = "All Branches - YTD"
                        && [Fiscal Year] = EARLIER ( 'Table'[Fiscal Year] )
                        && [Fiscal Month]
                            = EARLIER ( 'Table'[Fiscal Month] ) - 1
                )
            )
    )

The result is:

Hope this helps you. Here is my PBIX file.

Best Regards,

Community Support Team _Yinliw

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