U.S. stocks extended gains on Monday, with the three major indexes up more than 2 percent, after better-than-expected May U.S. manufacturing data sparked optimism the economy may have seen its worst days.

The Dow Jones industrial average <.DJI> added 174.43 points, or 2.05 percent, to 8,674.21. The Standard & Poor's 500 Index <.SPX> gained 17.98 points, or 1.96 percent, to 937.12. The Nasdaq Composite Index <.IXIC> rose 36.26 points, or 2.04 percent, to 1,832.35.