Calculation using a previous row within a hierarchy

Hi Anonymous ,

Based on your picture, I think it is the part of your data I will just focus on the forecast result ignoring the sum value of other two fields [Retention] and [Enrolled].

Also, since the [Retention] is a measure, I have created a simple sum measure to imitate it in my sample file:

Retention = SUM('Table'[value])

To get the previous row value in this case to calculate the forecast value, you can create this measure:

Forecast =
VAR tab =
    SUMMARIZE (
        'Table',
        'Table'[Department],
        'Table'[Class],
        'Table'[Block],
        'Table'[Enrolled],
        "prows",
            VAR _pre =
                CALCULATE (
                    MAXX ( 'Table', [Retention] ),
                    FILTER (
                        ALL ( 'Table' ),
                        'Table'[Department] IN DISTINCT ( 'Table'[Department] )
                            && 'Table'[Class] IN DISTINCT ( 'Table'[Class] )
                            && 'Table'[Block]
                                = CALCULATE (
                                    MAX ( 'Table'[Block] ),
                                    FILTER (
                                        ALL ( 'Table' ),
                                        'Table'[Department] IN DISTINCT ( 'Table'[Department] )
                                            && 'Table'[Class] IN DISTINCT ( 'Table'[Class] )
                                            && 'Table'[Block] < MAX ( 'Table'[Block] )
                                    )
                                )
                    )
                )
            RETURN
                IF ( ISBLANK ( _pre ), 0, _pre )
    )
RETURN
    SUMX ( tab, [prows] * [Enrolled] )

Attached my sample file in the below, hopes to help you.

Best Regards,
Community Support Team _ Yingjie Li
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