Fifteen years is a long time, but it hasn’t been enough to erase the poor average annual returns of growth stock mutual funds for that period. The average growth mutual fund rose an average annual 0.58% in the past 15 years vs. 7.28% for its value-style counterpart, 6.83% for core funds and 4.38% for the S&P 500, according to Morningstar Inc. What does that mean in dollars?