DAX Calculated Column for Last Delivery Date

Hi Power-CJ ,

I am very sorry, I have modified my program, please try again.

Column =
VAR _1 =
    CALCULATE (
        MAX ( 'Table'[Index] ),
        FILTER (
            ALL ( 'Table' ),
            'Table'[Index] < EARLIER ( 'Table'[Index] )
                && 'Table'[Sell-to-Customer] = EARLIER ( 'Table'[Sell-to-Customer] )
        )
    )
VAR _2count =
    CALCULATE (
        COUNT ( 'Table'[Shipment Day] ),
        FILTER (
            'Table',
            'Table'[Shipment Day] = EARLIER ( 'Table'[Shipment Day] )
                && 'Table'[Sell-to-Customer] = EARLIER ( 'Table'[Sell-to-Customer] )
        )
    )
VAR _shang2 =
    CALCULATE (
        MIN ( 'Table'[Index] ),
        FILTER (
            'Table',
            _2count > 1
                && 'Table'[Sell-to-Customer] = EARLIER ( 'Table'[Sell-to-Customer] )
                && 'Table'[Shipment Day] = EARLIER ( 'Table'[Shipment Day] )
        )
    )
VAR _nextday =
    CALCULATE (
        MAX ( 'Table'[Shipment Day] ),
        FILTER (
            'Table',
            'Table'[Sell-to-Customer] = EARLIER ( 'Table'[Sell-to-Customer] )
                && 'Table'[Index] = _1
        )
    )
RETURN
    IF (
        _2count > 1
            && 'Table'[Index] = _shang2,
        _nextday,
        IF ( _2count > 1 && 'Table'[Index] <> _shang2, BLANK (), _nextday )
    )

If it does not help, please provide more details with your desired output and pbix file without privacy information (or some sample data) .

Best Regards
Community Support Team _ Polly

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