Investing.com - Stocks have been stuck in a volatile trading range since the correction of February, but one Wall Street firm says that will soon yield to another move higher.In a note to clients, the Wells Fargo (NYSE:WFC) Investment Institute says technical data indicate a breakout and "a resumption of the trend that was in place before the correction."The firm points to the fact that on several recent occasions the S&P 500 has closed above its 200-day moving average, which is viewed as a key indicator for determining long-term price trends. Wells says history shows that once a breakout begins investors will feel a sense of "missing out" on the market gains and invest new money, pushing prices even higher.The firm has a year-end, price target for the S&P 500 of 2,950, which is about 3% higher than the index's record peak in late January.