While the United States still ranks as its fastest growth audience, Facebook traffic in the US declined significantly last month, according to the latest figures released by Inside Facebook, a site dedicated to tracking the social networking site for developers and marketers.

As its user ranks approach 700 million worldwide, Facebook traffic in the United States has dropped off by nearly 6 million users, according to statistics from Inside Facebook Gold analytics service, the research arm of Inside Facebook, which gets its information from Facebook’s advertising tool

The second largest growth audience after the US is Indonesia, with about 36.4 million users, followed by the United Kingdom, which has 29.9 million users. The US. accounts for 155.2 million users, or 23.6 percent of growth over the past 12 months.

New Facebook users totaled 11.8 million people in May, compared with13.9 million who joined in April, and an average of about 20 million in the 12 months prior, according to Inside Facebook’s latest statistics.

The number of US Facebook users fell from 155.2 million to 149.4 million during the month of May alone – “nearly 6 million people who decided they no longer need to stay connected through the service, and is the first time Facebook has lost users in the last year,” a Digital Trends report said.

Another report suggests that with an impending IPO, Facebook could be focusing its user growth in the North American and China markets.

“As Facebook targets 1billion users, many have focused on China as its great untapped source of growth. But as Facebook’s investors target an initial public offering next year, the health of the network in more immediately profitable areas such as North America and Western Europe might be just as big a concern,” blogged the Financial Times’ Tim Bradshaw.

Inside Facebook ranks Facebook audience growth data on a monthly basis. 

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Erin Harrison is Executive Editor, Strategic Initiatives, for TMC, where she oversees the company's strategic editorial initiatives, including the launch of several new print and online initiatives. She plays an active role in the print publications and TechZone360, covering IP communications, information technology and other related topics. To read more of Erin's articles, please visit her columnist page.

Edited by Jennifer Russell