U.S. stocks are skidding as another day of big losses takes the market to its lowest level in more than a year and more in Monday’s Stock Market Update. Retailers and technology stocks are sinking, and health insurers and hospitals are falling after a federal judge in Texas ruled that the 2010 Affordable Care Act is unconstitutional.

Some of the biggest losses are going to utilities and real estate companies, which have done better than the rest of the market during the turbulence of the last three months.

The price of oil closed below $50 a barrel for the first time since October 2017.

STOCK MARKET UPDATE

The S&P 500 skidded 54 points, or 2.1 percent, at 2,545 at closing time. The Dow Jones Industrial Average lost 505 points, or 2.1 percent, to 23,592. The Nasdaq composite fell 156 points, or 2.3 percent, to 6,753. The Russell 2000 index dipped 37 points, or 2.7 percent, to 1,373.

The S&P 500 dropped in early trading and briefly recovered before falling again. It’s now on track for its lowest close since October 2017. The U.S. benchmark index has fallen more than 13 percent since it set a record high in late September. The Russell 2000 has done significantly worse: it’s down 20 percent since it finished at its last record high at the end of August. Wall Street calls a 20 percent decline a “bear market,” and it’s considered a major downturn.

The S&P Small Cap 600 index went into a bear market Friday as investors continue to lose confidence in the U.S. economy’s growth prospects. Smaller companies are considered more vulnerable in a downturn than larger companies because they are more dependent on economic growth and tend to have higher levels of debt.

Hospital operator HCA dropped 3.2 percent to $122.69 while health insurer UnitedHealth lost 2.9 percent to $257.27. Centene, a health insurer that focuses on Medicaid and the Affordable Care Act’s individual health insurance exchanges, fell 5.1 percent to $121.07 and Molina skidded 10.2 percent to $118.30.

Many experts expect the ruling will be overturned, but with the markets suffering steep declines in recent months, investors didn’t appear willing to wait and see.

Bond prices rose. The yield on the 10-year Treasury note fell to 2.85 percent from 2.89 percent.

The Federal Reserve is expected to raise interest rates again Wednesday, the fourth increase of this year. It’s been raising rates since over the last three years, and investors will want to know if the Fed is scaling back its plans for further increases based on the turmoil in the stock market over the last few months and mounting evidence that world economic growth is slowing down.

The S&P 500’s index of financial stocks is down 10 percent in the last month, worse than any other part of the market. For the year it’s down 14 percent, much worse than the 4.2 percent decline in the S&P 500.

OVERSEAS STOCK MARKET UPDATE: British Prime Minister Theresa May said Parliament will vote Jan. 14 on her deal setting terms for Britain’s departure from the European Union. She canceled a vote on the deal last week because it was clear legislators were going to reject it. May insists she can save the deal, but pressure is mounting for either a vote by lawmakers or a new referendum on the issue.

Britain is scheduled to leave the EU in late March, and if it does so without a deal in place governing their trade and economic relationships, it could bring huge disruptions to the British and European economies and financial markets.

Germany’s DAX lost 0.9 percent. That means the DAX, which represents Europe’s largest single economy, is also in bear market territory. France’s CAC 40 and Britain’s FTSE 100 both fell 1.1 percent.

Japan’s Nikkei 225 index added 0.6 percent and the Kospi in South Korea gained 0.1 percent. Hong Kong’s Hang Seng was less than 0.1 percent lower. Both the Kospi and Hang Seng are in bear markets as well.

China and the United States clashed again over their respective trade policies Monday, as China criticized what it calls a “unilateralist and protectionist” approach to trade. The U.S. ambassador to the World Trade Organization said those critiques were unwarranted. The two nations have been embroiled in a dispute over technology policy and other issues for most of this year. With no end to the conflict in sight, investors are growing more concerned that the tensions will drag down the already-slowing global economy.

Benchmark U.S. crude fell 2.6 percent to $49.88 a barrel in New York. Brent crude, used to price international oils, dipped 1.1 percent to $59.61 a barrel in London.

Wholesale gasoline shed 1.7 percent to $1.41 a gallon and heating oil slid 1 percent to $1.83 a gallon. Natural gas dropped 7.8 percent to $3.53 per 1,000 cubic feet.

Gold rose 0.8 percent to $1,251.80 an ounce. Silver added 0.8 percent to $14.76 an ounce. Copper dipped 0.3 percent to $2.75 a pound.

The dollar slipped to 112.75 yen from 113.29 yen. The euro rose to $1.1350 from $1.1303. The British pound rose to $1.2629 from $1.2579.

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