facebook-140903_640When news hit that Facebook coughed up $19 billion for the messaging app, WhatsApp, a lot of people wondered if Facebook was a little sick in the head.

It was the largest amount Facebook was known to pay for an acquisition of a company (, ) and cost more than the market capital of companies likeĀ Gap and Harley Havidson.

But it also shows that Facebook is trying to tap into text within emerging markets, where most people largely use their phones for messaging (). For example in China, where 95% of Chinese citizens surveyed said they had a cell phone, 80% of them use it for messaging than for other uses ().

It’s a strategy that might prove worthwhile as the percentage of Facebook users slows in the U.S. According to Pew Research, 71% of online adults used Facebook in 2013, only a slight increase from the 67% in 2012.

But time will tell if it was worth the price tag that is twice the market cap of Best Buy.

Check out the interactive graphs below for more information.

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