Many people incorrectly equate indexing with a strategy of simply buying the S&P 500 Index. That is no longer the only game in town. The S&P 500 omits the thousands of small companies that are among the most dynamic in the economy. Thus, I believe that if an investor is to buy only one U.S. index fund, the best general U.S. index to emulate is one of the broader indexes such as the Russell 3000, the Wilshire 5000 Total Market Index, the CRSP Index, or the MSCI U.S. Broad Market Index—not the S&P 500.
