Because similar patterns are observed for many other languages (but not all), it looks like  R.Stuart Geiger explanation is correct: from October 16 2014 Special:Random page is just not counted any more (with some not clear exceptions).

That’s a pity because we lost valuable source of info how Wikipedia users look for information. Random search was (and is?) a major way users explore Wikipedias. In many languages Special:Random was significantly higher than Main_Page count and certainly higher than search with index.php.

(I do not want to point finger, but maybe somebody at WMF considered this emotionally.)

IMHO, logs should be logs and log actual activity.  At least such dramatic changes in logging user’s activity should be documented somewhere. Betters in file that should accompany raw logs. 

>Date: Mon, 11 May 2015 20:08:40 -0700
>From: "R.Stuart Geiger" <>
>To: Research into Wikimedia content and communities
>        <>
>Subject: Re: [Wiki-research-l] Wiki-research-l Digest, Vol 117, Issue
>        14
>        <>
>Content-Type: text/plain; charset="utf-8"
>Going from 86,000,000 a month to 31,000 a month is quite a drop, and the
>shift is pretty dramatic. It goes from 1.7 million one day to 715 the next
>and stays flat (
>I was also thinking there could be a bot or something that is scraping
>Special:Random, but the drop also happens for Special:Random/Talk -- which
>hardly anybody uses, but it still drops flat the same day (
> It doesn't happen for
>Special:Upload or Special:Log though.
>October 16th, 2014 is the day it changes. Anybody know of something that
>might have changed that day with logging? Also, there have to be way more
>than ~1,000 hits a day to Special:Random. Perhaps pageviews started to be
>counted for the page that it got redirected to, rather than the
>Special:Random page itself. But then why wouldn't it go to 0? What are
>those ~1,000 hits a day?
>👻 ~~ it is a mystery ~~ 👻

Thank you.

Alex Druk
(775) 237-8550 Google voice