Is your stomach strong enough to take a flier on bitcoin?

The value of the virtual currency can fluctuate wildly—even in a single day. From July 2010 to February 2014, its price was 26 times more volatile than the S&P 500, according to Matt Elbeck, a marketing professor at Troy University in Alabama, who co-wrote a recent study about bitcoin with a colleague, Chung Baek.

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