Hi,
These counters have been removed from MediaWiki (the software the wiki is running on) as of the latest version. We've updated our installation today, which is why you're no longer able to view them. See
https://m.mediawiki.org/wiki/Requests_f ... aWiki_core for the discussion on that decision (note that it's not something we've decided ourselves). There are extensions available that can takeover the functionality of the counters, but as we've only just updated to a major new release, I'll stay away from installing new addons for a day or two to ensure everything's running fine.
Just out of curiosity: what did you use the counter for?
Cheers,
Gijs