Wall Street lost ground Thursday as influential technology stocks fell and once again steered the broader market.

The technology sector has been the driving force behind the market’s direction, whether up or down, all week. Thursday’s losses pushed nearly every major index solidly into weekly losses. If that momentum holds on Friday, it would break a three-week winning streak for the S&P 500, the Dow Jones industrial average and the Nasdaq composite.

The S&P 500 fell 75.97 points, or 1.1%, to 6,720.32. The Dow fell 398.70 points, or 0.8%, to 46,912.30. The Nasdaq fell 445.80 points, or 1.9%, to 23,053.99.

The biggest weights on the market included Nvidia, which fell 3.7%, and Microsoft, which fell 2%. Their huge values give them outsized influence over the market’s direction. Other big stocks dragging down the market included Amazon, which slumped 2.9%.

DoorDash sank 17.5% for one of the sharpest drops on Wall Street. The food delivery app warned investors that it will be spending significantly more on product development next year.

CarMax slumped 24.3% after giving investors a disappointing financial update and announcing that CEO Bill Nash is stepping down in December.

Software company Datadog jumped 23.1% after its latest earnings beat analysts’ forecasts. Rockwell Automation rose 2.7% after turning in results that easily beat analysts’ forecasts.

The latest round of earnings is being closely monitored to gauge whether the stock market’s big values are justified. The results are also helping to fill in gaps in information because of the U.S. government shutdown, which is now the longest on record.

Another week of unemployment data was missing Thursday because of the shutdown.

The U.S. government shutdown is having a direct impact on airlines, as airports face critical staffing problems. The Federal Aviation Administration will reduce air traffic by 10% starting Friday across 40 “high-volume” markets. American Airlines fell 2%, Delta Air Lines fell 1.2% and United Airlines fell 1%.

Treasury yields moved lower in the bond market. The yield on the 10-year Treasury fell to 4.09% from 4.16% late Wednesday. The yield on the two-year Treasury fell to 3.56% from 3.63% late Wednesday.

— Associated Press