Calculate variance from previous date

Hi, gr84 

Based on your description, If you have a date column, you can create following new columns to achieve the effect you are looking for. Following picture shows the effect of the display.

New columns:

Previous Count =

CALCULATE (

    MAX ( 'Table'[Value] ),

    FILTER ( 'Table', 'Table'[Date] = EARLIER ( 'Table'[Date] ) - 1 )

)

Variance =

IF (

    'Table'[Date] = MIN ( 'Table'[Date] ),

    BLANK (),

    'Table'[Value] - 'Table'[Previous Count]

)

If this does not work, could you please share some sample data without sensitive information and expected output.
How to provide sample data in the Power BI Forum - Microsoft Fabric Community

Best Regards,
Yang
Community Support Team

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If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!

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