The Dow Jones industrial average rose 186 points Friday as a deal to forge stronger ties between most of Europe's economies raised hopes that the region is close to resolving its debt crisis.
All 17 nations that use the euro agreed to sign a treaty that allows a central European authority closer oversight of their budgets. Nine other EU nations are considering it. Britain is the lone holdout.
The Dow closed up 186.56 points, or 1.6 percent, at 12,184.26.
The Standard & Poor's 500 index closed up 20.84 points, or 1.7 percent, at 1,255.19.
The Nasdaq composite index finished up 50.47, or 1.9 percent, at 2,646.85.
For the week:
The Dow rose 164.84 points, or 1.4 percent.
The S&P rose 10.91 points, or 0.9 percent.
The Nasdaq rose 19.92 points, or 0.8 percent.
For the year to date:
The Dow is up 606.75 points, or 5.2 percent.
The S&P is down 2.45 points, or 0.2 percent.
The Nasdaq is down 6.02 points, or 0.2 percent.