NEW YORK ( TheStreet) -- In the 1990s, academic researchers showed that low-priced value stocks had outdone more expensive growth names over long periods. That encouraged many investors to emphasize value stocks.Some of the most popular ETFs in recent years have been value choices, including iShares Russell 1000 Value ( IWD) and Vanguard Value ( VTV). But investors who put extra weight on value recently have had little to show for their efforts. During the past 10 years, the Russell 1000 Value index returned 6.7% annually, while the Russell 1000 Growth returned 6.8%. "The difference between growth and value is not as great as many investors have been led to believe," says Paul Baiocchi, an analyst for IndexUniverse.com. "It didn't really matter whether you took growth or value because the patterns of returns have been so similar." Instead of emphasizing a growth or value fund, investors might as well buy the whole market, says Baiocchi. If investors want to fine tune their portfolios, then they can get more distinctive results by using funds that specialize in a sector, such as energy or financials. "If you are looking to make a call on the economy or lower the volatility of your portfolio, you should use sectors instead of growth or value funds," he says. In a recent study, Baiocchi and Paul Britt looked at the past performance of the major sectors of the S&P 500 as well as growth and value segments. They found that the growth and value portfolios tended to act much like the S&P 500 -- and the correlations have been increasing in recent years. The researchers found that each sector has delivered distinctive returns. During the past 10 years, financials lost money, while utilities more than doubled. During the financial crisis, all sectors dropped at once. But since then, the sectors have resumed following distinctive courses. During 2011, the gaps in performance were especially wide. For the year, Consumer Staples Select Sector SPDR ( XLP) returned 14.1%, while Energy SPDR ( XLE) returned 2.8%, and Industrial SDPR ( XLI) lost 1.1%. This year the Utilities SPDR ( XLU) returned 0.7%, while Technology SDPR ( XLK) returned 15.4%.