The New York Stock Exchange, the world's largest equity market, resumed trading Wednesday after a two-day suspension forced by a Hurricane Sandy power outage that has paralyzed much of lower Manhattan. 

The bourse is the primary exchange for many blue-chip issues and, though it handles only about 11 percent of U.S. stock trading, is critical in setting the opening and closing prices of benchmarks used by investors around the world.

Wednesday's opening followed a series of electronic tests on Tuesday calculated to assess the exchange's ability to handle trading.