Steve Massocca, managing director at Wedbush Securities, said the easy central bank policies will act as a floor for the stock market though it is stuck in a range. "The market is going to be in a trading range. It's stopped by valuation at this level, and it's helped by incredible monetary policy at lower levels," he said. "There's probably not going to be a change in aggressive monetary policy, so going back to early 2015, the market's pretty much been in the same valuation range. We're at the high end of the range. I'm not saying the market's going to roll over and go back to where it was in early 2016."