Stocks fall, swelling September’s losses.

A long list of worries caught up with Wall Street in September, the stock market’s worst month since the early days of the pandemic.

After a 1.2 percent slide on Thursday, the S&P 500 ended down 4.8 percent for the month, its sharpest monthly decline since March 2020, and one that snapped a seven-month streak of gains.

Until the recent decline, investors had shaken off the emergence of the coronavirus’s Delta variant, problems with a backed-up supply chain and persistent inflation, with the S&P 500 rallying to a Sept. 2 record and a dizzying 21 percent gain since the beginning of the year. But stocks started to slide as concerns grew about political gridlock leading to the U.S. defaulting on its debt and as instability in China’s real estate market shook Wall Street.

With investors also eyeing the Federal Reserve’s plans to start slowing its purchases of government-backed bonds, yields on the 10-year Treasury note jumped to their highest levels in months, reaching 1.55 percent on Wednesday.

Large technology stocks, which have an outsize influence on the major stock indexes and which typically fall as bonds become more appealing to investors, saw double-digit drops. Apple ended the month nearly 10 percent off its Sept. 7 record.

Adding to jitters earlier in the month were concerns that a default by China Evergrande Group would ripple through global markets. The company, which has about $300 billion in debt, faced several payment deadlines. Those concerns eased somewhat in recent days, in part as the company said that it was selling a stake it held in Shengjing Bank for about $1.5 billion, with the proceeds going toward paying down its debts.

Retail stocks were among the worst performing on Thursday. The used vehicle retailer CarMax dropped nearly 13 percent, while Gap closed 8 percent lower. Bed Bath & Beyond slid about 22 percent after the company slashed its forecasts for sales and earnings.

Supply chain constraints continued to squeeze these companies, with many anticipating delays and shortages of goods, along with higher prices tied to labor and already skyrocketing shipping costs. Consumer confidence is at its lowest level in seven months, the Conference Board reported on Tuesday.

Concerns about retailers were magnified this month with factories in Vietnam forced to close or operate at severely reduced capacity as coronavirus cases surged. Power cuts and blackouts have also slowed or closed factories across China this week.

“Lingering supply chain constraints have become a major hurdle to inventory restocking,” Lydia Boussour, lead economist at Oxford Economics, wrote in a note. “Assuming the global virus situation gradually improves, we expect the bottlenecks will ease in 2022 as production ramps up and shipping congestion starts to clear.”

The sentiment was also voiced by Jerome H. Powell, the Fed chair, as he noted in Senate testimony on Wednesday that while demand was strong in the United States, factory shutdowns and shipping problems were pushing inflation above the Fed’s goal of 2 percent on average.