Stocks went into a steep slide Thursday after Apple sent a shudder through Wall Street with word that iPhone sales in China are falling, reinforcing fears that the global economy is weakening.

On Thursday:

The S&P 500 index sank 62.14 points, or 2.5 percent, to 2,447.89.

The Dow Jones Industrial Average slid 660.02 points, or 2.8 percent, to 22,686.22.

The Nasdaq composite surrendered 202.43 points, or 3 percent, to 6,463.50.

The Russell 2000 index of smaller-company stocks lost 25.07 points, or 1.8 percent, to 1,330.83.

For the week:

The S&P 500 is down 37.85 points, or 1.5 percent.

The Dow is down 376.18 points, or 1.6 percent.

The Nasdaq is down 121.02 points, or 1.8 percent.

The Russell 2000 is down 7.09 points, or 0.5 percent.

For the year:

The S&P 500 is down 58.96 points, or 2.4 percent.

The Dow is down 641.24 points, or 2.7 percent.

The Nasdaq is down 171.77 points, or 2.6 percent.

The Russell 2000 is down 17.73 points, or 1.3 percent.