There’s a good reason America’s most popular social networks are looking for new users overseas.

A new study from Pew Research Center found that social networks like Instagram, Facebook and Twitter are all slowing down considerably when it comes to adding U.S. adult users. Pew reported the percentage of Internet-using adults for each network on Wednesday, and while Facebook, Instagram and Pinterest all increased (slightly) since 2014, the percentage of U.S. adults on Twitter didn’t change from 2014. LinkedIn’s number actually decreased, from 28 percent to 25 percent.

The networks that did show growth did so in small increments. Instagram, for example, jumped from 13 percent to 28 percent of U.S. adults since 2012, but it only jumped from 26 percent to 28 percent in the past year. Facebook, which dwarfs the other networks by claiming 72 percent of U.S. adults as users, rose just 1 percent since last year.

Here’s what that slowdown looks like:

These numbers shouldn’t come as a surprise to those who follow these companies. U.S growth overall has been slowing for Twitter and Facebook over the last few years. It’s why bringing on more international users remains such a high priority. Facebook, for example, is working to provide free Internet access to people in emerging markets like South America and Africa (you can’t access Facebook without the Internet, after all). Twitter is working to make its service more accessible to those without wireless Internet, too, and recently started sharing user figures for those who receive tweets as text messages (a popular method in India).

The study contained a handful of other statistics, including a rise in mobile messaging apps. More than one third (36 percent) of smartphone-wielding adults in the U.S. use a mobile messaging app like Kik or WhatsApp, Pew found. It’s the first time Pew has collected this data, a nod to the growing popularity of standalone messaging apps. (Kik just raised $50 million from Tencent on Tuesday.)