Gustavo Caballero | FilmMagic | Getty Images The 2012 Sports Illustrated Swimsuit Issue billboard is unveiled in New York's Times Square.

The 2012 Sports Illustrated issue was revealed Monday, featuring 19-year-old American model and actress, Kate Upton, on this year's magazine cover. 

Could the cover of the most profitable single-issue magazine franchise in the world be a barometer for the stock market? CNBC.com looked at the market performance in years when the magazine cover featured a blonde versus a brunette. 

The models' hair color was gauged from the Sports Illustrated website, dating back to 1964. 

>> QUIZ: Test Your Swimsuit Issue IQ

49 covers from 1964 until now:

• 25 blonde covers — average annual return of Dow 10 percent, S&P 10.9 percent
• Note: The covergirl from 2008, Marissa Miller, is a blonde and the Dow and S&P fell 34 and 39 percent, respectively
• 20 brunette covers — average annual return of Dow 2.2 percent, S&P 2.3 percent
• 3 covers with multiple models of varied hair color
• 1 cover with a redhead

Additionally, the models' nationality may also yield an interesting result.  Since 1978, the S&P 500 posted an average return of 14.3 percent when an American was on the cover of the magazine versus an 10.8 percent increase when a model from another country was selected, according to Bespoke Investment Group.

The following pages contain the Sports Illustrated covers associated with the best market years.

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