Facebook is falling behind in the youth movement. New data shows the social media giant is losing its appeal with teenagers in the U.S., specifically to the photo-sharing app Snapchat.

A new study by the research firm eMarketer found that in 2017 alone, Facebook lost 1.4 million users between the ages of 12 to 17 — a roughly 10 percent drop for that demographic, Recode notes. The fall was even worse than what eMarketer had predicted, having anticipated just a 3.4 percent drop in users aged 12 to 17, Recode reports — and even that modest downturn was the first time eMarketer had ever projected declining user rates for Facebook across any age group.

Most observers agree that there are two factors that are largely responsible for Facebook's teenage exodus: the loss of the ever-important "cool" factor, and teenagers' preference for Snapchat. Facebook's "cool" — or lack thereof — is widely attributed to its appeal among older generations. What growth Facebook is seeing is among older users rather than younger ones, CNBC reported — a "predicament" for the social app, eMarketer's Debra Aho Williamson told CNBC.

By comparison, Snapchat is thriving. Even after it rolled out a widely panned redesign, Snapchat expects to add 1.9 million users under the age of 25 in 2018. Meanwhile, Facebook could lose 2 million in that same demographic, CNBC reports.

While Facebook is losing its hold on the all-important teen demographic, eMarketer still predicts that Facebook's overall user share in the U.S. will grow. Facebook still boasts nearly 170 million American users, compared to Snapchat's 86.5 million. Kelly O'Meara Morales