NEW YORK ( TheStreet ) -- Many investors dream of making a killing with an initial public offering. But the track record of IPOs is discouraging.During the 1990s bull market, a crowd of fledging Internet companies soared and then crashed. Last year, Facebook's (FB) troubled launch served as a reminder that even strong companies can flop on their first day. In a recent study, T. Rowe Price tracked 4,500 companies that went public between 1995 and 2007. Of those that had less than $100 million in revenue on the first day of trading, only one out of 20 grew to $1 billion in revenue.
Of the companies that survive the initial screens, the index includes the 100 largest. The portfolio is rebalanced every quarter. Companies that drop below the top 100 rankings are eliminated and new stocks join. Holdings can stay in the index for up to 1,000 trading days, or about four years. Because it emphasizes the biggest companies, the portfolio includes many familiar names with long track records. Among the top 10 holdings are General Motors (GM), Kraft Foods (KRFT) and Hyatt Hotels (H). Besides IPOs, the index can also include spinoffs. Those occur when a company sells or distributes a subsidiary. Stocks of spinoffs often perform well because newly independent managements cut costs and focus on core businesses.