Though the English Wikipedia reached three million articles in August 2009, the growth of the edition, in terms of the numbers of new articles and of editors, appears to have peaked around early 2007.[38] Around 1,800 articles were added daily to the encyclopedia in 2006; by 2013 that average was roughly 800.[39] A team at the Palo Alto Research Center attributed this slowing of growth to the project's increasing exclusivity and resistance to change.[40] Others suggest that the growth is flattening naturally because articles that could be called "low-hanging fruit"—topics that clearly merit an article—have already been created and built up extensively.[41][42][43]
