U.S. stocks abruptly changed course again Tuesday and took large losses. Investors worried about the possibility of a weaker global economy and tried to anticipate the Federal Reserve’s plans for interest rates. Energy companies fell with the price of oil after a leading industry group said demand for oil is down more than it previously thought.

On Tuesday :

The Dow Jones industrial average tumbled 258.32 points, or 1.4 percent, to 18,066.75.

The Standard & Poor’s 500 index dropped 32.02 points, or 1.5 percent, to 2,127.02.

The Nasdaq composite shed 56.63 points, or 1.1 percent, to 5,155.25.

For the week:

The Dow is down 18.70 points, or 0.1 percent.

The S&P 500 is down 0.79 points, or 0.04 percent.

The Nasdaq is up 29.35 points, or 0.6 percent.

For the year:

The Dow is up 641.72 points, or 3.7 percent.

The S&P 500 is up 83.08 points, or 4.1 percent.

The Nasdaq is up 147.84 points, or 3 percent.