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Here's a hint: It's not the U.S. Not even close, in fact. Just 5 percent of Americans report they've gone nude at the beach.

German beachgoers led the world in beach brazenness; a full 17 percent of Germans reported having sunbathed naked on a public beach. And it seems the number of German skinny dippers are on the rise: The nation took the title in 2012, too, but at that time 15 percent admitted to sunbathing in the buff.

Online travel agency Expedia last week released the results of the 2013 Flip Flop Report, an annual study of behavior and preferences among beachgoers in North America, South America, Europe, Asia and Australia. Some 8,606 consumers who had either taken a beach vacation in the past year or plan to do so in the next year participated in the 2013 study across 21 countries. Harris Interactive, conducting the study online on Expedia's behalf, asked global consumers to opine on a wide range of beach-related questions, such as comfort with nudity, fear of sharks and tolerance of bathing suits such as a Speedo.

More results:

Most Likely to Build a Sandcastle: India

Most Likely to Have Wallet/Possessions Stolen: U.S.

Most Likely to Have a Fear of Drowning: Malaysia

Most Likely to Say a Speedo is Acceptable Swimwear: France

Least Likely to Be Comfortable with Topless Sunbathing: India

Least Likely to Avoid the Water Because of Shark fear: U.S.