If you have an online brokerage account, you can now buy shares in a fund that aims to track the price of the digital currency called bitcoin. Just don’t expect a smooth ride.

Bitcoin is a highly speculative investment—the kind most financial advisers say investors should only buy into with money they can afford to lose. But some analysts think the new fund could bring the digital currency a step closer to broader acceptance by investors. For that to happen, the fund will have to overcome some early difficulties.

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