The Standard & Poor’s 500 Index fell into a correction for the first time since 2011 in one of the most volatile trading days ever, as a rout in global equity markets deepened.

It was a day of wild swings as equities plunged at the open before staging a sharp rebound, with the Nasdaq 100 Index by midday nearly erasing a 9.8 percent drop. The Dow Jones Industrial Average dropped 1,000 points in the opening minutes of trading, and the S&P 500 tumbled 5.3 percent and then pared declines before an afternoon wave of selling.

The S&P 500 dropped 3.9 percent to 1,893.39 at 4 p.m. in New York, and was 11 percent below its May record.

The Chicago Board Options Exchange Volatility Index rose 44 percent to 40.42, trimming an earlier 90 percent surge that temporarily sent the index to its highest level since January 2009. The gauge known as the VIX more than doubled last week, soaring 118 percent to 28.03.

The S&P 500’s rout sent valuations tumbling. The price-to-earnings ratio for the gauge sank to 16.76, the lowest level since the October pullback. Then, the measure bottomed just above 16.50, the cheapest since January 2014.

Source : Bloomberg