[NEW YORK] US stock indexes plunged almost 4 per cent on Monday as investors, rattled about China's economy, sold heavily in an unusually volatile session that confirmed the S&P 500 was formally in a correction.
The Dow Jones industrial average briefly slumped more than 1,000 points, its most dramatic intraday trading range ever, with key component Apple falling heavily only to claw back and end down 2.5 per cent.
It was the S&P 500's worst day since 2011 and followed an 8.5 per cent slump in Chinese markets, which sparked a sell-off in global stocks along with oil and other commodities .
Wall Street had stayed in a narrow range for much of 2015, but volatility jumped this month as investors became increasingly concerned about a potential stumble in China's economy and after Beijing surprisingly devalued its currency, the yuan.
Some investors unloaded stocks ahead of the close after looking to make money from volatile price swings earlier in the session. "If things don't settle down in China, we could have another ugly open tomorrow and you wouldn't want to be caught holding positions you bought this morning," said Randy Frederick, managing director of trading and derivatives for Charles Schwab in Austin.
Apple's Chief Executive Tim Cook, in comments to CNBC, took the unusual step of reassuring shareholders about the iPhone maker's business in China ahead of a dramatic 13-per cent drop and rebound in its stock, which closed down just 2.5 per cent at US$103.12.
The Dow Jones industrial average closed down 588.4 points, or 3.57 per cent, at 15,871.35.
The S&P 500 lost 77.68 points, or 3.94 per cent, to 1,893.21, putting it formally in correction mode.
An index is considered to be in correction when it closes 10 per cent below its 52-week high. The Dow was confirmed to be in a correction on Friday.
The Nasdaq Composite dropped 179.79 points, or 3.82 per cent, to 4,526.25, also in a correction.
Futures for Hong Kong's Hang Seng index were down 2.1 per cent, suggesting that more bleeding may be in store when trading begins again in Asia.
The CBOE Volatility index, popularly known as the "fear index", briefly jumped as much as 90 per cent to 53.29, its highest since January 2009.
Preliminary data from BATS Global Markets show 1,287 trading halts on US stock exchanges on Monday due to excessive volatility or tripping of circuit breakers, far more than usual.
The S&P 500 index showed 187 new 52-week lows and just two highs, while the Nasdaq recorded 613 new lows and eight highs. "Emotions got the best of investors," said Philip Blancato, chief executive at Ladenberg Thalmann Asset Management in New York. "The conjecture that the Chinese economy can propel the US economy into recession is ridiculous, when it's twice the size of the Chinese economy and is consumer-based." All of the 10 major S&P 500 sectors were down, with energy losing 5.18 per cent.
US oil prices were down about 6 per cent at 6-1/2-year lows, while London copper and aluminum futures hit their lowest since 2009.
Exxon and Chevron each fell more than 4.7 per cent. US oil and gas companies have already lost about US$310 billion of market value this year.
The dollar index was down 1.72 per cent. It fell more than 2 per cent earlier to a seven-month low as the perceived probability of a September US interest rate hike receded.
Traders now see a 24 per cent chance that the Federal Reserve will increase rates in September, down from 30 per cent late on Friday and 46 per cent a week earlier, according to data from inter-dealer money broker Tullett Prebon.
Wall Street's sell-off shows investors are becoming increasingly nervous about paying high prices for stocks at a time of minimal earnings growth, tumbling energy prices and uncertainty around a Fed rate hike.
Alibaba lost 3.49 per cent to US$65.80, below its IPO price of US$68, making it the second high-profile tech company to fall below its IPO price in the past week after Twitter on Thursday.
Declining issues outnumbered advancers on the NYSE 3,064 to 131. On the Nasdaq, 2,632 issues fell and 281 advanced.
Volume was heavy, with about 14.0 billion shares traded on US exchanges, double the 7.0 billion average this month, according to BATS Global Markets.