Why your mutual fund is probably a loser

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Stock pickers had a brutal 2015, and there is little wonder why.

It's hard to beat the market when you're not on board with the best-performing companies. Such was the fate of mutual fund managers, who again fell short of their benchmarks over the past 12 months.

In a year that many had touted as ripe for the return of stock pickers, just 27 percent of large-cap core funds topped the S&P 500, according to a recent Goldman Sachs analysis. That number falls well below the 10-year average of 36 percent.

The root of the problem is pretty simple: Most managers were underweight many of the stocks that saw the biggest gains.

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Specifically, managers missed the boat on Netflix and Amazon, the two best performers on the with respective returns of 140 percent and 117.6 percent as of Monday's market close. They also underallocated to Starbucks (up 46.7 percent), Facebook (up 35.8 percent), General Electric (22.3 percent) and Microsoft (up 20.4 percent).