Howard Marks, CEO of private-equity firm Oaktree Capital Group, described his company's going public last month as a "humbling experience." Oaktree's initial public stock offering hit the market at the bottom of its proposed range and has fallen 8 percent since (the stock was offered at $43 and this week was trading for $39.70). "Humbling" would be putting it mildly if you were to describe the performance of private-equity firms that have gone public over the past few years. The S&P Listed Private-Equity Index, made up of 25 public firms that buy stakes in privately held companies, is down 44 percent over the past five years. The S&P Index, by comparison, is flat.