12 years ago today, Mark Zuckerberg launched Facebook, and since then the site has grown at a nearly unbelievable pace. Now, with about 1.6 billion monthly active users, Facebook makes an average of $3.73 in revenue per user worldwide. And as the company continues to grow, engagement is only getting higher. According to an analysis by CNBC, users spend an aggregate of 10.5 billion minutes per day on the social media platform -- that's around $3.5 trillion in squandered productivity, by their estimate. Facebook is celebrating its birthday by marking today "Friends Day" and adding personalized videos to each user's account showing their best moments with friends, or at least what Facebook's algorithms think are the best moments. (Users can opt to share the video or keep it private.) The company's also announced an updated degrees-of-separation metric to make it easier to connect with other users.