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But in recent weeks, it's been particularly challenging with correlations, or the degree two stocks are moving in concert, surging to their highest levels in years.
In other words, it doesn't matter how good you are at picking stocks because the whole market is increasingly swinging in the same direction.
"Leaving few stocks unscathed, recent equity turbulence drove S&P 500 stock correlations from 30% to 56%, the highest levels since the 2011 European crisis," said Goldman Sachs' David Kostin. "As correlations spiked, return dispersion - measured as the cross-sectional standard deviation of stock returns - fell, leaving bottom-up stock pickers with a diminished opportunity set for generating alpha."
Kostin expects dispersion to remain low over the next few quarters, so selecting outperforming stocks will be tough.
However, Kostin and his team compiled a list of 35 stocks that have high "dispersion scores," which he describes as companies "much more likely to react to company-specific developments rather than the macro environment."
Below are the 16 companies with high dispersion scores with current prices offering over 25% upside relative to Goldman Sachs analysts' price targets.