I see from the title, you do mean the source media area. This area will only show events for which a source media file is loaded and ready to populate the event.
If you only have seven source media files loaded, you will only see seven events, one for each source media file. If you untick one of the source media files, it will only show six events.
If you have no source media files loaded, the box will be empty regardless of the events defined within the template.
Hope this helps. Mick.