Dynamic Standard Deviation

Hi jackj ,

Please try below steps:

1. create a measure with below dax formula

Standard Deviation of the Total Sales =
VAR cur_country =
    SELECTEDVALUE ( 'Table'[Country] )
VAR max_date =
    MAXX ( 'Table', [End of Week] )
VAR min_date =
    MINX ( 'Table', [End of Week] )
VAR tmp =
    FILTER (
        ALL ( 'Table' ),
        'Table'[Country] = cur_country
            && 'Table'[End of Week] >= min_date
            && 'Table'[End of Week] <= max_date
    )
RETURN
    CALCULATE ( STDEV.P ( 'Table'[Total Sales] ), tmp )

 2. add some visuals like below

Please refer the attached .pbix file.

Best regards,
Community Support Team_Binbin Yu
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