Calculated column using 'lookup' in same table

Hi Steven-conance ,

According to your screenshot, I think we can determind [Period] based on [Week Start Date]. My code is based on this logic, we will calculate week start date based on today and then get period. Then use this dynamic period in switch.

Please try it to create a calculated column.

Passed/Current/Future Periods =
VAR _WeekStart_Date =
    TODAY () - WEEKDAY ( TODAY (), 2 ) + 1
VAR _Period =
    CALCULATE (
        SUM ( 'TableName'[Period] ),
        FILTER ( 'TableName', 'TableName'[Week Date Start] = _WeekStart_Date )
    )
RETURN
    SWITCH (
        TRUE (),
        [Period] > _Period, "Future",
        [Period] = _Period, "This Period",
        [Period] < _Period, "Past"
    )

Best Regards,
Rico Zhou

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