Joel Greenblatt's "magic formula investing" strategy trounced the Standard & Poor's 500 index during the 10-year period ending June 30.

An investor who started with $10,000 on July 1, 1999, and used the magic formula method ended up with $29,400, according to the updated results published this week. That's a 194 percent total return, or 11.4 percent annualized. The figures are net of a 1 percent annual management fee.

The same investor who bought an index fund based on the S&P 500 would have ended up with $8,000, or a 20 percent loss.

The magic formula also beat the S&P for the one-, three- and five-year periods ending June 30. That's based on a back-tested magic formula portfolio of 24 top-ranked large-cap U.S. stocks rebalanced quarterly.

Greenblatt introduced his "magic formula" in "The Little Book That Beats The Market." The formula ranks stocks based on just two factors: return on capital and earnings yield.

Investors who are intrigued by the logic and simplicity of the magic formula can open a free account at magicformulainvesting.com that allows them to see what stocks meet Greenblatt's parameters. The list, which is updated daily, can be adjusted based on market cap.

The formula's current list of 30 stocks among the biggest equities includes a number of equities that guru investors have chosen. Check out the site to see for yourself.

Greenblatt says in the book that the magic formula list could be looked at as just a starting point for stock ideas. It's certainly one of the simplest methods an investor can use, and a good starting point for people new to the market.