Recently we've got Special:Import enabled for transwikis from some others mediawiki wikis (https://bugzilla.wikimedia.org/show_bug.cgi?id=38943).
But apparently the article counter (NUMBEROFARTICLES) is not incremented once for each imported article, but once for each revision of the imported article!
So if I import an article with 100 revisions in the version history NUMBEROFARTICLES goes up by 100 instead of by 1.
I hope this can be fixed and that the article counter can be reset to it's actual value (it seems this needs to be done by someone with shell access [according to this related but different bug report: https://bugzilla.wikimedia.org/show_bug.cgi?id=5703]). I assume this also affects other wikis and it just went unnoticed because other wikis deal with higher article creation rates so the unusual article number bumps were covered by regular article creations and went unnoticed? Please check and update the article counters of the other wikis too if this applies.
Thank you very much for your time