There is a new plugin for that:
Plugin: Best users per month
It provides a widget and a page (and you can tell your users about rewards).
Check out the install instructions!
Welcome to the Q&A site for Question2Answer.
If you have a question about Q2A, please ask in English.
To report a bug, please create a new issue on Github or ask a question here with the bug tag.
If you just want to try Q2A, please use the demo site.
July 15, 2020: Q2A 1.8.5 released!