This Is the Single Craziest Number in Facebook’s Earnings Report

Facebook put up a lot of impressive numbers in its third quarter earnings report Tuesday: 1.35 billion monthly active users, $3.2 billion in revenue, $800 million in profit. But the number that may be most surprising is one that rarely gets harped on in the media: 864 million daily active users.

This figure is the true metric driving the company’s runaway growth. To make money, Facebook needs to serve you ads—lots of ads—as you peruse its site. Obviously these daily users are soaking up a lot more ads than people who just check in once a month. Perhaps more importantly, the figure shows that Facebook is able to maintain its hold on users’ attention even as it stuffs more features (like auto-playing videos) and ads onto its site. In fact, the percentage of daily active users in the quarter, out of the total number of monthly active users, was 63%, up from about 59% in the previous quarter.

This impressive retention rate helps explain why Facebook has said it will take on additional expenses in the future to expand staff and pursue more acquisitions—the company believes it knows what is users want, and it seemingly has the stats to back up the claim.

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