When administering your portal, you will have the ability to get a complete overview of the activity of all your users. There are two columns in the Manage User's page that will enable you to determine how many service hours a user has done and the length of time they are registered to do in the near future.
Below are the column names and their descriptions:
Hours = Hours that someone has served/volunteered
Hours Registered = Events and opportunities they may have registered for and the hours it equals up to but they have yet to at