Bitcoin Plunges 29% From Record High Offshoot called bitcoin cash is luring users amid tech debate Bitcoin’s jump this year has attracted Wall Street’s interest Citigroup Inc. CEO Michael Corbat shares his thoughts on digital currencies. Bitcoin plunged as the cancellation of a technology upgrade prompted some users to switch out of the cryptocurrency, spooking speculators who had profited from a more than 800 percent surge this year. The cryptocurrency has dropped 9.5 percent since late Friday, extending its slide…