A laptop computer with the Facebook logo is seen on display at the offices of Facebook Inc.'s European headquarters at Hanover Quay in Dublin, Ireland, on Thursday, March 14, 2013. Ireland’s renewed competiveness makes it a beacon for the U.S. companies such as EBay, Google Inc. and Facebook Inc., which have expanded their operations in the country over the past two years. Photographer: Simon Dawson/Bloomberg
INTERNATIONAL - Facebook Inc. is losing its swagger with young users, who are increasingly migrating to rival platforms including Snap Inc.’s Snapchat, according to a new study.

Seventy-one percent of U.K. social network users between 12 years and 17 years old will be using Facebook regularly this year, a downgrade of 8 points from last year’s forecast, EMarketer Inc. said Monday, citing its own report. 

Children are increasingly moving to Snapchat, which will get log-ins from 43 percent of U.K. social networkers in 2018, more than double the rate of three years ago.

In the U.S. last year, 68.5 percent of social media users at age 12 to 17 years old used Facebook, down from 90 percent in 2013, according to EMarketer. Eighty-nine percent were using Snapchat, up from 29 percent four years ago.

Facebook has tried to stem an exodus to Snapchat with measures such as a new version of its Messenger app for children. While the overall number of Facebook users in the U.K. will reach 32.6 million this year -- far more than Snapchat, Instagram or Twitter can claim -- the drop among younger users means Facebook’s "teen issue" is more than just a theory, said Bill Fisher, an analyst at EMarketer.

“There are now some early signs that younger social networkers are being swayed by Snapchat,” Fisher said. “The challenge and opportunity for Snap is how to appeal beyond that core youth demographic.”

Technology companies are also facing increasing pressure to address their impact on the mental health of children. In an open letter to Apple Inc. dated Jan. 6, activist investor Jana Partners LLC and the California State Teachers’ Retirement System urged Apple to create ways for parents to restrict children’s access to their mobile phones. They also want the company to study the effects of heavy usage on mental health.