The user tracker allows you to see all your users within your account (this can be filtered by groups and subaccounts too) and see some general information about each user. For example, we can see that 4 users have completed all sims, only Michael Lee has yet to do one of the two he was shared. No one has failed any of the sims shared to them. If you click on a users row, you will be taken to the Activity Tracker for a more granular view.
You can add a date range here to filter the users that have been shared your sims between those dates. Be sure to click "show results" once you have inputted a date range.
Opposed to this, you can filter the users that have attempted or completed a sim within this date range.
This will remove any date filters from both the Date Shared and Activity Date fields, resulting in all the reporting data for all your users to be shown here.