How quickly has Facebook grown globally? Researchers at Nielsen collected some markers to help everyone following today’s IPO get a grasp on the stunning numbers involved.

In its native United States, two out of every three online people visited Facebook in March 2012. That’s 152 million unique visitors.

It got there quickly, too. Facebook doubled its U.S. traffic every year between 2005 and 2009, crossing the psychologically significant 10 million mark sometime before November 2006 (when it had 11.6 million uniques). Myspace was still king of the social network world then, however – Facebook didn’t claim that crown until January 2009.

This pattern is not exclusive to the U.S. Looking again at the 10 million mark, Facebook reached that in the U.K. by April 2008, followed the following year by France (January 2009), Spain (May 2009) and Germany (November 2009).

It took until August 2011 for Facebook to surpass Orkut as the top social networking site in Brazil, and it still ranks “only” fifth of the services in Nielsen’s social media category for Japan. Even so, that means Facebook leads that category in all but one of the 12 markets on the chart below.

Related link:

Nielsen – blog post

Photo by Flickr user Kevin Krejci, used under Creative Commons license