From a Wikimedia Post:
The gender distribution of Wikipedia editors hasn’t changed since the last survey [April 2011]. Among those surveyed, 90 percent self-identified as males, 9 percent as females and 1 percent as transsexual or transgender. That being said, there was a greater amount of female editors among those respondents who had joined more recently: Among editors who had joined in 2011, 14 percent were female compared to 10 percent for 2010, 9 percent for 2009 and 8 percent for editors who had joined in 2008 and participated in this survey. Possible explanations include that Wikipedia has been attracting a higher ratio of women recently, or that female editors leave the project sooner. There were no significant variations across the major language Wikipedias, with the exception of the Russian Wikipedia, which reported only 6 percent female editors. Also, out of all editors in the US, 15 percent are women, which is significantly higher than any other country of residence. Conversely, there are fewer male editors in US (85 percent) compared to other countries (UK, India, Brazil, Canada) where 90 percent or more of editors are males. With initiatives like the Teahouse project that engages new editors through outreach, we hope to increase the number of female editors on Wikipedia.
As we had found in the April 2011 survey, a large majority of Wikipedia editors read and edit the English version. Many editors that primarily make edits to another language Wikipedia also edit the English Wikipedia. While only 30 percent primarily edit the English Wikipedia, 63 percent contribute to it. Almost half of English Wikipedia editors reported other language Wikipedias as their primary project. Similarly, 86 percent of Wikipedia editors read the English Wikipedia, though only 38 percent read it primarily.
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