If you're wondering why the Discovery Channel is still pumping out a week's worth of shark-related content after 30 YEARS, here's your answer:  Over the past two years, Shark Week has brought in $36 MILLION in ad money.

The 2017 total was $20.2 million . . . which was 59% more than Discovery's average weekly revenue of $12.7 million that year.

Shark Week 2018 starts Sunday night at 7:00 P.M.  Celebs on hand this year include Shaquille O'Neal, Ronda Rousey, Aaron Rodgers, Rob Gronkowski, Lindsey Vonn, Guy Fieri, Bear Grylls, and the cast of ABC's "Shark Tank".

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