How Facebook dominates the internet

Mark Zuckerberg is now worth more than $55bn. Photo / AP

As companies grow, they are supposed to reach a point where the law of large numbers forces them to slow down: eventually, the pool of potential customers is supposed to run out.

But Facebook's fourth-quarter results, published on Wednesday night, continued to defy logic. It now has close to 2 billion members using it every month, more than half the world's internet population, and more than doubled profit.

Facebook's userbase is bigger than the population of China and more than half the estimated 3.5 billion people who have internet connections. This is particularly staggering because Facebook is cut off to China's population, suggesting the vast majority of the non-Chinese world uses it.

Revenue: £21.8 billion last year

Facebook continues to take up much of the entire internet advertising market. Last year it took in $27.6bn (£21.8bn) in sales, a 54 per cent increase on a year ago.

Much of this has been due to the rise of mobile advertising - something Facebook didn't even have five years ago when it floated. In the last quarter, mobile adverts made up 84 per cent of all revenue. By some accounts, Facebook accounts for 43 per cent of all digital advertising growth.

Total value: £306 billion

When Facebook floated in 2012 at a $100 billion valuation, it had people warning about a new tech bubble, and at first they looked right, as shares steadily declined to half their IPO price.

Since then, though, the company's spectacular string of results means that its value has almost quadrupled to around $385 billion (£306 billion), making it the world's sixth biggest company and giving Mark Zuckerberg a net worth of some $57.4bn.

Average revenue per user: £12.65 last year

Facebook may be signing up more users, but it is also making more money off each one. In the fourth quarter it made $4.83 per person and in the whole of last year, $15.92 (£12.65).

In Europe, the average revenue per user was even higher at around £15.05: in the UK it is believed to be close to £50.

Facebook's other giants: 1 billion and 600 million

It would be enough for Facebook to own the world's biggest social network, but it also owns the competition. The world's next most popular social network in the West is Instagram at 600 million users, and the world's biggest chat app is WhatsApp.

Both are owned by Facebook and were picked up for $1bn and $19bn respectively. Given the growth since they were acquired, they both look like a bargain.