Counting Unique Values

I am building a participation tracking system and got stuck. We have RFID badges that can be scanned into Excel to track attendance. I have set up that part with no problem. I am trying to set up a dashboard to easily see attendance. I currently have all scans going to a table so I can turn them into pivot tables for the dashboard. However, since my system tracks every instance of attendance a value is counted more than once. Example, 1 person attends an exercise class on 7/27/2020 and then attends the same class again on 7/29/2020. It will show up that the resident attended the class twice, which is correct and I want to track that. However, I also want it to show that the 1 person has attended the class from a historical perspective. I need help to be sent in the right direction for formulas so that I can 2 things: There were a total of 10 attendance for this class and it was attended by 4 different people.

I know this can be completed using countif and sumproduct but I want this to be shown on 1 single dashboard that is able to be filtered by slicers.

Thank you

Hello jrod59 and Welcome to Excel Forum.
It may help someone to better understand if we could see a sample .xlsx file, instructions are given in the banner at the top of the page.
Remember to manually produce the results that you would like to see automated in the dashboard.
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