U.S. stocks recovered some of their losses Friday following a steep slide in early trading, but the drop was enough to push the benchmark S&P 500 index back into the red for the year.
Despite the afternoon rebound, stocks were still on track to erase much of the market's gains from a big rally the day before and to finish a week of unusually turbulent trading with hefty losses.
Longtime market favorites like Amazon and Alphabet, Google's parent company, led the way lower after reporting weak results. Technology and consumer-focused companies accounted for much of the sell-off. Media and communications stocks, health care companies and banks also took heavy losses.
The Dow Jones Industrial Average fell more than 300 points and the S&P 500, the benchmark for many index funds, is now down 9.4 percent from its September peak. Bond prices rose, sending yields lower, as investors seek less risky assets.
The stock market has whipsawed this week, with the Dow slumping 500 points over the first two days of the week, plunging 608 on Wednesday, soaring 401 points Thursday and then plunging again on Friday. The ups and downs came during the busiest week for third-quarter company earnings.
"We're going through this transition where, earlier in the year, the corporate earnings results were just a blowout and now they're more mixed," said David Lefkowitz, senior equity strategist Americas at UBS Global Wealth Management. "That's causing some of this volatility."
The S&P 500 index slid 48 points, or 1.8 percent, to 2,656 as of 3:48 p.m. Eastern Time. The index is now headed for its worst month since February 2009, right before the stock market hit bottom following the 2008 financial crisis.
The Dow dropped 307 points, or 1.2 percent, to 24,676. The average was briefly down more than 500 points.
The tech-heavy Nasdaq composite lost 163 points, or 2.2 percent, to 7,154. The Russell 2000 index of smaller-company stocks gave up 17 points, or 1.2 percent, to 1,483. The S&P 500 is now down for the year again.
Stock trading turned volatile in October after a placid summer, with big sell-offs in the sectors that have powered the bulk of the gains during the market's long bull run. Disappointing quarterly results and outlooks have stoked investors' jitters over future growth in corporate profits, a key driver of the stock market. Traders are worried that rising interest rates and the escalating U.S.-China trading dispute could hurt the economy and dampen corporate earnings growth.
Amazon and Google parent company Alphabet slumped after both companies reported quarterly reported revenue figures that fell short of analysts' estimates. Amazon sank 8.5 percent to $1,631.10 while Alphabet fell 2.8 percent to $1,072.25.
Mattel dropped 2.7 percent to $13.61 after the toy maker served up quarterly results that fell short of analysts' forecasts.
Colgate-Palmolive lost 6.9 percent to $59.43 after the maker of consumer products didn't earn as much revenue in the latest quarter as analysts expected.
In a bright spot, chipmaker Intel gained 3.1 percent to $45.71 after it reported strong quarterly results and raised its outlook.
The Commerce Department said the U.S. economy's gross domestic product, a measure of total output of goods and services, grew at a robust annual rate of 3.5 percent in the July-September quarter. That's higher than what many economists had been projecting and followed an even stronger 4.2 percent rate of growth in the second quarter. The two quarters marked the strongest consecutive quarters of growth since 2014.
U.S. bond prices rose. The yield on the 10-year Treasury note fell to 3.07 percent from 3.13 percent late Thursday.
Benchmark U.S. crude rose 0.4 percent to settle at $67.59 a barrel in New York. Brent crude, the benchmark for international oil prices, added 0.9 percent to close at $77.62 a barrel in London.
Wholesale gasoline gained 0.1 percent to $1.82 a gallon. Heating oil jumped 1.1 percent to $2.30 a gallon and natural gas fell 0.5 percent to $3.19 per 1,000 cubic feet.
The dollar fell to 111.85 yen from 112.61 yen on Thursday. The euro rose to $1.1412 from $1.1359.
Gold rose 0.3 percent to $1,235.80 an ounce. Silver gained 0.5 percent to $14.70 an ounce. Copper dipped 0.5 percent to $2.74 a pound.
Major European stock indexes fell. Germany's DAX slipped 0.9 percent, while France's CAC 40 dropped 1.3 percent. Britain's FTSE 100 slid 0.9 percent. In Asia, Japan's benchmark Nikkei 225 lost 0.4 percent, while South Korea's Kospi dropped 1.8 percent. Australia's S&P/ASX 200 was flat. Hong Kong's Hang Seng sank 1.1 percent.