The activity tracker allows you to see each attempt of a user for a specific sim, or all sims (you can select "all sims" from the dropdown menu). You can see above that William Brooks attempted "BTT Induction - Advanced" twice, failing the first time with 67% score, and then passing the second time with 94% in 7 minutes and 9 seconds.
You can filter the users that have attempted or completed a sim within this date range. Be sure to click "show results" once you have inputted a date range.
This will remove any date filters from the Activity Date field, resulting in all the reporting data for all your user to be shown here.