New York ? Wall Street topped off a strong week with a big rally Friday, after results from companies such as Citigroup Inc. and Google Inc. helped ease investor anxiety about the health of corporate profits.

The Dow Jones industrial average jumped 228.87, or 1.81 percent, to 12,849.36. The Standard & Poor’s 500 index increased 24.77, or 1.81 percent, to 1,390.33, and the Nasdaq rose 61.14, or 2.61 percent, to 2,402.97.

The gains come at the end of a big week for stocks. For the week, the Dow rose 4.25 percent, the S&P 500 gained 4.31 percent and the Nasdaq jumped 4.92 percent.

Gold prices fell, while the dollar was mixed against other major currencies.