US stocks rallied late on Wednesday to end a choppy session close to where they began as investors waited cautiously for the start of the earnings season, due to open after the bell with results from Alcoa.

The aluminium maker gained 1.6 per cent on an otherwise bearish Tuesday after Klaus Kleinfield, the chief executive, said he was “very optimistic” about sales. The stock swung on Wednesday as investors bet on whether the company would beat its estimates, and ended the day 0.5 per cent up at $9.46.