Dynamic Measure calculation

lbendlin , thanks for your concern about this case. I tried to create a sample data myself based on the user's requirement and implemented the result. Please check if there is anything that can be improved. Here is my solution:
Hi  NMDGA ,

I created some data:

Here are the steps you can follow：

When the same columns are used in the slicer and the table visual, then the table visual will change with the values selected by the slicer, and we can create a table of dates with no relationship to work with measure

1. Create calculated table.

Date =
CALENDAR(
    DATE(2024,7,1),
    DATE(2024,10,31))

2. Create measure.

Flag =
var _select=SELECTEDVALUE('Date'[Date])
return
IF(
    MAX('Table'[report date])=_select ||
    AND(
        MAX('Table'[report date])<_select,MAX('Table'[activeflag])="Y"),1,0)

3. Place [Flag]in Filters, set is=1, apply filter.

4. Result:

Best Regards,

Liu Yang

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