Fewer than one in five U.S. large-cap mutual funds beat the benchmark S&P 500 index in the first quarter. The average margin of underperformance—1.9 percentage points—also set a new low. Growth fund managers fared even worse, with just 6% of growth funds beating their benchmark—the worst such result since at least 1991. The average margin of underperformance was 3.5 percentage points. Read the original story from The Motley Fool.