Create selectable categories for numeric slicer

Hi ReadTheIron ,

I agreed with amitchandak 's suggestion—— You have to create an independent table using those three values. 

And I have entered a table as shown below:

Then please use the following formula to create a flag measure:

Flag =
VAR _sum =
    CALCULATE (
        SUM ( 'Table'[Total Impact] ),
        ALLEXCEPT ( 'Table', 'Table'[Incident ID] )
    )
RETURN
    SWITCH (
        MAX ( 'ForSlicer'[Catrgory] ),
        "20+", IF ( _sum > 20, 1 ),
        "50+", IF ( _sum > 50, 1 ),
        "All", 1
    )

Apply it to filter pane ,set as "is 1", the final output is shown below:

Best Regards,
Eyelyn Qin
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