Tesla's shares fell 8.6 percent on Monday, wiping $15.2bn (£10.8bn) off the fortune of the richest person in the world. With a $183bn estimated fortune behind Jeff Bezos, Elon Musk dropped back into second place. His comments came just two weeks after Tesla purchased Bitcoin for $1.5bn, which sent the price to new highs. On Sunday, Bitcoin reached a high of $58,000 but has fallen to $47,500 on Tuesday morning since then. Over the past year, the price is still more than 500% higher.