adding new rows in table with condition

Hi sam_hoccane ,

According to your description, I create a sample.

Here's my solution.

1.Create a new table. Make relationship with the two tables, the Year Month column in the two tables both should be of date type.

2.Create a measure.

Measure Value =
IF (
    MAX ( 'Table'[Value] ) <> BLANK (),
    MAX ( 'Table'[Value] ),
    MAXX (
        FILTER (
            ALL ( 'Table' ),
            'Table'[Year Month ] = MAXX ( ALL ( 'Table' ), 'Table'[Year Month ] )
        ),
        'Table'[Value]
    )
        * POWER (
            1.2,
            DATEDIFF (
                MAXX ( ALL ( 'Table' ), 'Table'[Year Month ] ),
                MAX ( 'Table (2)'[Year Month] ),
                MONTH
            )
        )
)

Get the result.

I attach my sample below for reference.

Best Regards,
Community Support Team _ kalyj

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