Oh, it's good to be back. Movie buffs may associate that line with Robert Downey as he Tony Starked his way down to Earth in 2010's "Iron Man 2," but investors are more likely to be thinking of this year's market for initial public offerings. 💵💰Don't miss the move: Subscribe to TheStreet's free daily newsletter 💰💵 As of Aug. 21 the Renaissance IPO Index was up 11.7% year-to-date, while the S&P 500 was up 9.2%. The investment firm said that 143 IPOs have priced this year, up 55.4% from a year ago. The I ...