Kate Upton will once again be on the cover of the Sports Illustrated Swimsuit Issue, only this time, it will mark the publication's commemorative 50th anniversary.

Upton is only the ninth model to appear on the coveted front page twice and only the fifth to be used in back-to-back years. The 2013 issue is expected to outperform the Michigan native's 2012 issue. To top it off, many people believe it will surpass Sports Illustrated's best-selling issue - its 25th anniversary edition with Kathy Ireland on the cover in 1989.

The Sports Illustrated Swimsuit Issue features a combination of sex, finance and sports. Since 1997, a majority of the sporty spread has been dedicated to swimsuit models in exotic locations donning revealing bikinis. The magazine's featured edition normally sells above 1 million copies and represents roughly 7 percent of the company's advertisement revenue in terms of retail, fashion design, photography, locations and modeling, according to PolicyMic.

CNBC said the publication is the "most profitable single-issue magazine franchise in the world."

"If a swimsuit makes it into the issue, it can elevate the brand tremendously and have a huge impact on sales," Keith Bielory, a social media and marketing consultant, told Forbes.

The swimsuit layout was created in 1964 as a way to generate sales during the slower winter months of the sports publication, at a time where the NBA wasn't yet popular or the NFL season extended into February.

The company's managing editor Andre Languerre is known for coming up with the idea. However, Julie Campbell is given credit for transforming the issue into the media frenzied pictorial piece that it is today. 

Campbell, a fashion reporter, began using "bigger and healthier" California models and identifying them by name, which can arguably be attributed to the supermodel era.

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