The S&P 500 index briefly rose 2 percent on Wednesday, rebounding from recent losses as a bullish earnings forecast from State Street Corp encouraged investors ahead of the earnings season.

Equities have been pressured in recent weeks, with the Dow Jones industrial average down seven of the past eight sessions as concerns persist about the strength of the global economy.

The Dow was <.DJI> was up 176.80 points, or 1.81 percent, at 9,920.42. The Standard & Poor's 500 Index <.SPX> was up 19.71 points, or 1.92 percent, at 1,047.77. The Nasdaq Composite Index <.IXIC> was up 35.26 points, or 1.68 percent, at 2,129.14.

(Reporting by Angela Moon; Editing by Padraic Cassidy)