The Dow Jones industrial average closed with a gain of 115 points on Friday, finishing at a one-month high. Investors expect that the central banks of countries around the world stand ready to head off a deeper European debt crisis.
Greece holds a crucial election on Sunday that will help determine whether that country abandons the euro.
The Dow Jones industrial average jumped 115.26 points, or 0.9 percent, to close at 12,767.17.
The Standard & Poor's 500 rose 13.74 points, or 1 percent, to 1,342.84.
The Nasdaq composite rose 36.47 points, or 1.3 percent, to 2,872.80.
For the week:
The Dow is up 212.97 points, or 1.7 percent.
The S&P 500 is up 17.18 points, or 1.3 percent.
The Nasdaq is up 14.38 points, or 0.5 percent.
For the year:
The Dow is up 549.61 points, or 4.5 percent.
The S&P 500 is up 85.24 points, or 6.8 percent.
The Nasdaq is up 267.65 points, or 10.3 percent.