This plugin was a part of the main Cotonti package before v.0.9.8.
It is a standalone page with various statistics for forums module, such as total number of posts, topics, most viewed and most replied topics, most active users.
Author: Cotonti team
GitHub: https://github.com/Cotonti-Extensions/forum-stats
Add link or button to forum statistics page to your template
<a href="{PHP|cot_url('plug', 'e=forumstats')}">{PHP.L.forumstats_title}</a>