Facebook lost almost one third of its U.S. teen users in 2013, according to a newly released edition of one of the most comprehensive social media studies.
The report highlights Facebook's continued dominance of the social media world as well as the broader pivot of social media users to mobile, but it adds another data point to the growing perception that teen use has moved to popular new messaging apps like WhatsApp and Snapchat.
Facebook endured a 29% fall in active users among U.S. teens from fourth quarter 2012, when 79% of all U.S. teens contributed to the site, according to data prepared for Mashable from the report.
This decline was primarily at the beginning of 2013. From Q3 to Q4 in 2013 the decline leveled off, but active teen users still fell 11%. U.S. teens were not markedly different from the global trend that has caused concern among Facebook analysts and investors.
The GlobalWebIndex Social Q1 2014 study, which polled 170,000 social media users in 32 countries, shows that Facebook is still the dominant social network in the world. Despite the drop in teen use, GlobalWebIndex founder Tom Smith told Mashable the idea that Facebook has completely lost teens is misleading.
"The concept that [Facebook] is 'dead and buried' is obviously completely false," he said.
Facebook has recently been the subject of major concerns about the lack of teen activity on the site. One recent study said Facebook had lost one quarter of its teen audience, and another research proclaimed the site "dead and buried" among teens, although he later clarified his statement concerned a small group from the UK.
Even President Barack Obama said as much during a recent sitdown with young Americans.
Facebook, along with YouTube, experienced a decline in overall active users of 3% from the second quarter to the fourth quarter of 2013.
That decline is offset by Facebook-owned photo sharing app Instagram, which was the fastest growing social media entity at the end of last year with a 23% rise in active use. Reddit came in second with growth of 13%, following by LinkedIn at 9%.
Chinese microblogging site Tencent Weibo also had active user growth of 9%.
An active user is defined by GlobalWebIndex as a person who has used or contributed to the service in the past month.
The study also found a decline in computer use of social networks that was offset by growth in mobile users.
"Pretty much everything on a PC is in decline, and everything on mobile is growing," Smith said.
This has been particularly good for messaging and networking apps. Between the second and fourth quarters of 2013, WeChat grew its audience by 379%, Vine added 105%, Snapchat gained 54% and WhatsApp rose 35%.
The shift to mobile has also been embraced by the larger social networks. Active users of the Facebook app grew 69% in the fourth quarter of 2013 and YouTube rose by 59%.