Displaying previous value instead of blank

Hi JKoivu 

You can use a measure to get the result.

Previous quantity = 
VAR __previousDate =
    CALCULATE (
        MAX ( 'Quantity by date'[Date] ),
        FILTER (
            ALL ( 'Quantity by date' ),
            'Quantity by date'[Date] < MAX ( 'Calendar'[Date] )
                && 'Quantity by date'[Product ID] = MAX ( 'Products'[Id] )
        )
    )
RETURN
    CALCULATE (
        SUM ( 'Quantity by date'[Quantity] ),
        FILTER (
            ALL ( 'Quantity by date' ),
            'Quantity by date'[Date] = __previousDate
                && 'Quantity by date'[Product ID] = SELECTEDVALUE ( 'Products'[Id] )
        )
    )

If you calculate previous quantity in a calculated column, you should also use a measure to get the corresponding previous quantity column value when you hope to use a slicer to switch it.

Regards,
Community Support Team _ Jing
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