Analysts are predicting that the S&P 500 pension funds will be underfunded this year by close to $250 billion. Through the 1990s, the booming stock market resulted in pension plans seeing big gains without companies having to make contributions. After the stock market crash, pensions plans of companies in the S&P 500 went from being overfunded to underfunded. Companies were forced to find billions of dollars to meet their plans obligations, which in turn lowered their earnings per share. Complicated pension fund accounting overwhelms most investors, but new accounting rules that will take place next year will require companies to more fully disclose their pension plan allocations.