A Fund That Won by Tracking the Dow

NEW YORK ( TheStreet ) -- During the past ten years, S&P 500 index funds suffered through rough markets and then rebounded to deliver solid results. Over the decade, SDPR S&P 500 ETF (SPY) returned 8.0% annually, outdoing two-thirds of large blend mutual funds tracked by Morningstar. The strong record has not gone unnoticed. During the past year, shareholders poured $18.6 billion into the SPDR ETF, according to IndexUniverse.com.

But investors could have done even better with SPDR Dow Jones Industrial Average (DIA) , which returned 8.3% annually over the past ten years. The Dow Jones ETF seems particularly notable because it was less volatile than the S&P 500. During recent downturns, the Dow has outdone the S&P 500 by comfortable margins.

Should you dump your S&P 500 funds and shift to the Dow Jones choice? Not necessarily. The Dow average is a peculiar contraption that may not excel in every market. But there is a strong case for shock-proofing a portfolio by putting a limited amount of assets into the Dow.

Charles Dow created his index in 1896 by adding up the prices of 12 stocks. Since then, the benchmark has been expanded to include 30 leading companies that are broadly representative of the U.S. economy. A Dow Jones committee picks the names, seeking to find dominant businesses that should maintain their strong positions because of their competitive advantages.

The committee's judgments are subjective, and there are no mechanical rules dictating when new names must be included. Still, the committee has proven adept over the years, selecting rock-solid blue chips. The ETF now holds such reliable performers as Exxon Mobil (XOM) , Caterpillar (CAT) , and Coca-Cola (KO) .