According to A Random Walk Down Wall Street, there are many examples of funds that have consistently beat the market over 5-10 years, but there are very few tha

According to A Random Walk Down Wall Street, there are many examples of funds that have consistently beat the market over 5-10 years, but there are very few that outperform the market over a longer time horizon, and oftentimes they underperforming in the subsequent time periods (Peter Lynch's Magellan fund is the one counterexample given).