NEW YORK (AP) -- Stocks finished slightly lower Wednesday as health care companies continued to struggle. Energy companies rose as the price of natural gas surged on the first day of winter.
Some traders aren't sticking around to see if the Dow Jones industrial average reaches the 20,000-point milestone: trading volume has fallen sharply this week as the year-end holidays draw near.
After a mixed open, stocks finished at their lowest prices of the day. Health care companies continued to lag the market, as they've done throughout 2016. Industrial companies, which have surged since the presidential election, also eased lower. A jump of almost 9 percent in the price of natural gas helped gas and pipeline companies move higher.
"It looks like we're going to see another cold blast," said Jim Ritterbusch, an analyst who advises oil traders. He said weather forecasts suggest temperatures will drop later next week, which means people will use more natural gas to heat their homes.
The Dow dipped 32.66 points, or 0.2 percent, to 19,941.96. The Standard & Poor's 500 index lost 5.58 points, or 0.2 percent, to 2,265.18. The Nasdaq composite fell 12.51 points, or 0.2 percent, to 5,471.43.
Cancer drug maker Celgene dipped $2.67, or 2.3 percent, to $116.40 and Merck skidded $1.07, or 1.8 percent, to $59.43 while health insurance company Anthem lost $2.68, or 1.8 percent, to $144.98 as health care stocks fell. The S&P 500 health care index is down 4.4 percent this year. The S&P 500 itself is up almost 11 percent.
Natural gas companies made big gains thanks to a surge in natural gas futures. The price of that fuel climbed 28 cents, or 8.6 percent, to $3.54 per 1,000 cubic feet on the first day of winter. Southwestern Energy jumped 60 cents, or 5.8 percent, to $10.98 and Cabot Oil & Gas gained 62 cents, or 2.8 percent, to $22.44. Drilling service and pipeline companies also rose.
The price of natural gas has fluctuated sharply in the last few months.
"Whenever you get extreme volatility in the weather patterns, that translates to price volatility in futures," said Ritterbusch, the energy analyst.
FedEx said its quarterly expenses climbed and its earnings fell short of Wall Street estimates. The company's stock lost $6.62, or 3.3 percent, to $192.12.
Twitter slumped after Chief Technology Officer Adam Messinger said he's leaving the company. The struggling company has seen a number of executives leave recently. Former Chief Operating Officer Adam Bain left in November. In October Twitter said it would eliminate 9 percent of its workforce. Twitter fell 84 cents, or 4.7 percent, to $17.08.
AMC Entertainment took a step toward completing its purchase of competitor Carmike Cinemas. The Department of Justice said it will sign off on the sale if AMC sells 15 movie theaters in areas where it competes with Carmike. It will also sell most of its holdings in cinema advertising company National CineMedia and transfer 24 theaters to a rival theater ad company.
AMC agreed to buy Carmike in July for about $825 million in cash and stock in a deal that would make AMC the biggest movie theater chain in the U.S. Its stock rose $1.25, or 3.7 percent, to $34.70.
Mobile gyroscope maker InvenSense said it will be acquired by Japan's TDK Corp. for $13 a share, or $1.22 billion. That sent the stock to its highest price in almost a year and a half. InvenSense gained $1.91, or 17.6 percent, to $12.75.
Nike gained 51 cents, or 1 percent, to $52.30 after its second-quarter profit and sales came in stronger than analysts expected. Nike is by far the worst performer on the Dow this year. Its stock has tumbled 16 percent in part thanks to competition with Under Armour. Investors fear the rivalry is affecting both companies.
Benchmark U.S. crude fell 81 cents, or 1.5 percent, to $52.49 a barrel in New York. Brent crude, the international standard, lost 89 cents, or 1.6 percent, to $54.46 a barrel in London.
The dollar declined to 117.54 yen from 118.04 yen. The euro rose to $1.0427 from $1.0377.
Bond prices inched higher. The yield on the 10-year Treasury note slid to 2.54 percent from 2.56 percent.
In other energy trading, wholesale gasoline rose 1 cent to $1.61 a gallon. Heating oil lost 3 cents, or 1.7 percent, to $1.64 a gallon.
Gold fell 40 cents to $1,133.20 an ounce. Silver sank 14 cents to $15.98 an ounce. Copper remained at $2.50 a pound.
The CAC-40 in France gave up 0.3 percent. Britain's FTSE 100 and Germany's DAX finished little changed. In Hong Kong, the Hang Seng rose 0.4 percent and Tokyo's Nikkei 225 shed 0.3 percent. The South Korean Kospi retreated 0.2 percent.