Facebook's days of torrid growth in the U.S. appear to be behind it, according to one researcher.
ComScore reports that Facebook U.S. audience grew 5% in April, to 158 million. That was down from a 24% jump in April 2011 and a 89% growth in 2010.
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Meanwhile, users are spending more time on Facebook, but that growth is also slowing. In April, U.S. users spent six hours per month on the site, a 16% increase from the previous April. That compares to a 23% jump in April 2011 and a 57% rise in April 2010. Another recent survey from Reuters and research firm Ipsos found that 35% of users are less engaged with the site than they were in the recent past. Only 20% said they were spending more time on the site.
Facebook could not be reached for comment.
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With 71% of the U.S.'s estimated 221 million Internet users, Facebook doesn't have as much room to grow as it did a few years ago. The report also doesn't take into account expansion in international markets and on mobile. Facebook last disclosed in April that it's overall audience is 901 million and that the company is experiencing huge growth in some markets, like Brazil, that offset the U.S. figures.
Though U.S. users represent about a quarter of the company's base, the U.S. accounted for 56% of Facebook's ad revenues in 2011. Foreign markets haven't yet been picking up the slack, and Facebook has just begun monetizing its 488 million mobile users via targeted advertising. The question of whether Facebook will be successful in that endeavor has dogged its thus far disappointing IPO.
What do you think? Has Facebook lost some momentum? Do you spend less time on the site these days? Let us know in the comments.
Bonus Gallery: Facebook's IPO
2004: First Offers Turned Down
Facebook launches with humble beginnings that most people have seen dramatized in The Social Network by now. It was a small social site backed by only a little money, and limited just to the undergrads at Harvard. Right out of the gate, Facebook turned down offers from an unknown investor and Friendster, each offering $10 million. This was, of course, when the company was still called TheFacebook.
Image courtesy of Flickr.
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Image courtesy of iStockphoto, akinbostanci
This story originally published on Mashable here.

