Ubuntu Software Center - number badge indicator over 'Installed' tab

Hi all, I rarely use GUIs in Linux so I'm not that familiar with the Ubuntu Software Center and I am curious about an indicator I see on the "Installed" tab. It shows the number 1, but when I scroll down through the list of installed apps I don't see any other information or indicators. Anyone know how to hunt this down? Sorry I don't have more to go on; I usually solve all issues myself. This is not even an issue, but I have OCD and can't stand seeing stuff TODO or unknown. Screenshot provided.
USC_ERROR
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