Dynamic input for filters

Hi tbrown33 ,

I suggest you to use what if parameter to create a slicer.

For reference: Create and use what-if parameters to visualize variables in Power BI Desktop

In my sample I create a 'Past Days' parameter from 1 to 200 and Increment is 1. My data table contains quantities from 2021/01/01 to today. In my example, for ease of calculation, the daily quantity is 1.

Past N days Quantity = 
VAR _INPUT_DAYS =
    SELECTEDVALUE ( 'Past Days'[Past Days] )
VAR _QUANTITY =
    CALCULATE (
        SUM ( 'Table'[Quantity] ),
        FILTER (
            'Table',
            'Table'[Date] < TODAY ()
                && 'Table'[Date]
                    >= TODAY () - _INPUT_DAYS
        )
    )
RETURN
    _QUANTITY

Result is as below.

Past 7 days:

Past 180 days:

Best Regards,
Rico Zhou

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