Last week, the Wikimedia Foundation published some early results in an ongoing study of trends in editor participation, both in a detailed analysis by the survey’s leaders and a general summary by Wikimedia executive director Sue Gardner. I’d actually started writing a summary of my own before I read Gardner’s letter… only to find that Gardner had already made the exact same “Eternal September” comparison as I had planned. (Which makes sense, since I first learned of the term from Wikipedia.) Anyhow, both are worth reading if you are so inclined, but here’s a key excerpt from Gardner’s summary:

Between 2005 and 2007, newbies started having real trouble successfully joining the Wikimedia community. Before 2005 in the English Wikipedia, nearly 40% of new editors would still be active a year after their first edit. After 2007, only about 12-15% of new editors were still active a year after their first edit. Post-2007, lots of people were still trying to become Wikipedia editors. What had changed, though, is that they were increasingly failing to integrate into the Wikipedia community, and failing increasingly quickly. The Wikimedia community had become too hard to penetrate.

In the first half of Wikipedia’s first ten years, it experienced exponential growth in the absolute number of editors, from barely 100 active participants in 2001 to about 44,000 in 2006. The community continued to grow in 2007, cresting at nearly 52,000 active editors. Interestingly, though, 2007 brought fewer new editors: the peak owed to a one-year spike in retention. Thereafter, the number of total editors (and new editors) has dropped each year, with about 33,000 active contributors in 2010. Granted, that’s a pretty big drop. While it hasn’t bottomed out, it does seem to be stabilizing.

At the moment, Wikipedia has somewhat fewer editors than it had in 2006 and more than double the editors it had in 2005. But it only has slightly more new editors than it did that year: about 13,000 in 2010 compared to 12,200 new editors in 2005. For a better understanding of these trends, see this chart prepared for the survey:

Gardner continues:

Our new study shows that our communities are aging, probably as a direct result of these trends. I don’t mean that the average age of editors is increasing: I’m talking about tenure. Newbies are making up a smaller percentage of editors overall than ever before, and the absolute number of newbies is dropping as well. That’s a problem for everyone, because it means that experienced editors are needing to shoulder an ever-increasing workload, and bureaucrat and administrator positions are growing ever-harder to fill.

My initial reaction is to say this is not necessarily a problem. Yes, over time the proportion of new editors is shrinking, but this is the flipside of editor retention. The community “growing older” as a proportion of all editors does not necessarily mean number of editors is getting smaller, but that longtime editors are sticking around. Except that the community actually is getting smaller.

How many Wikipedians does the community really need to sustain itself? This is another open question. Some editors may point to the rapid development of impressive new articles such as Fukushima I nuclear accidents whereas interesting but less timely articles (let’s pick on the Assassination Records Review Board) languish.

If you joined Wikipedia in 2004, there is about a 40% chance you were still editing Wikipedia after one year. All things considered, that’s a pretty solid number, but that’s about as good as it got: by mid-2005 those retention rates started plummeting. If you joined in early 2007, there was about a 15% chance you were still editing after one year. Interestingly, the drop in retention more or less coincides with the explosion in new contributors: new editorship grew most between early 2005 and early 2007; the drop in retention begins about the same time and continued falling into the middle of 2007.

This makes some sense: those were the years with the greatest number of new editors, so it makes sense that a larger number would wash out. On the other hand, even as trends have stabilized, only about 10% of editors who joined in 2009 are still editing today. That’s a pretty remarkable drop-off in retention, and so the class of 2004 and 2009 today have about the same number of editors currently active.

Why the drop-off? Hard to say, but as the study’s authors put it: “[W]e do know something drastically changed during this time period, which corresponds to the period of massive influx of New Wikipedians.” This almost sounds like the influx of new editors drove the old ones out, although there’s no way to know that. So this raises an interesting question: were all those new editors necessarily good for the community?

For a snapshot of editor participation trends based on which year one joined, see this chart:

Wikipedia is an incredible resource and, like natural resources, it needs to be both developed and preserved. That means more editors are needed, and this study is just one step in a long process of figuring out how best to do that. Fortunately, there is time.