 Here's the Wall Street Business Report. Stocks closed lower, extending a slump that left Wall Street with its worst week since April. The S&P 500 fell 0.7%. Its third straight drop since setting a record high on Tuesday. The Dow sank 0.9% and the Nasdaq Composite lost 0.8%. The losses came as businesses around the world scrambled to contain the effects of a disruptive technology outage.