Is Facebook really worth $100 bn?

So is Facebook worth it? After a fevered day and evening reading the S-1 document filed with the US securities and exchange commission (SEC)- an event that proved so popular online that the SEC had to devote an extra server to handling demand - the answer seems to be that it's not worth $100 billion, but it might be worth $75 billion.

Facebook hit its stride in 2009, when revenues grew from $272 million to $777 million, and a $56 million net loss became a $229 million profit. Since then it has rapidly gained users, and the number of people on Facebook rose 39% to 845 million worldwide by the end of 2011.

For some, the idea that Facebook could be worth even $75 billion is laughable.

People are 'going to probably be overpaying by a third because of the optimism related to just the name', said Michael Yoshikami, chief executive of YCMNET Advisors, a California wealth management firm.

'The numbers justify maybe $50 billion,' he said. The company's revenue growth rate - up 88% over 2011, though it slowed between the first quarter and the fourth -would justify a $65 billion valuation, Yoshikami said.

Facebook revealed a host of data, as it is obliged to, as it seeks to raise $5 billion on the stock market. Its members use more than 70 languages. An incredible 57% of users - 480 million people - log in every day.

Analysts say it can't continue. 'The hypergrowth is probably over,' said Michael Pachter at Wedbush Securities. 'The low-hanging fruit of the western developed world' has already been grabbed, he said. 'It's just kind of obvious that they're not going to ever get every single person that lives on the planet.'

But if Mark Zuckerberg does harbour ambitions to reach everyone, then he will need to get them via mobile phones and that presents both an opportunity and a threat - because Facebook does not yet have a means of carrying advertising to those people.

Advertising is key to Facebook, accounting for 85% of revenues, with almost all the rest coming from Zynga, the maker of games such as Farmville.

The price of Facebook shares has not yet been set - that will emerge from talks with bankers keen to underwrite its offering.

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