That number is the finding of a new study that tried to quantify what the global offline population looks like. The report, based on research in collaboration with Facebook and written by the consulting firm McKinsey & Co., found that of the estimated 7 billion-plus people alive today, more than half are offline. This is after 1.8 billion people joined us here on the Internet since 2014.
The report is part of Facebook's efforts to expand Internet access to underserved parts of the world.