Markets unnerved by nearly 4-hour shutdown of NYSE

The New York Stock Exchange abruptly shut down at 11:32 a.m. EDT and remained down for almost four hours, unnerving investors. NYSE President Thomas Farley said the problem “likely had to do with an upgrade, but that is premature, and it’s something that will come about as part of a full analysis of the situation.” Trading of shares listed on NYSE continued on other markets, including Nasdaq.