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Surprise, surprise. A study shows that Americans like their music sexy.

The study analyzed the top-selling country, pop and R&B songs in 2009, for lyrics that had “reproductive messages” — otherwise known as references to sex and its consequences. And, perhaps unsurprisingly to Katy Perry and LMFAO fans, the vast majority of those best-selling songs had sexy references.

“Approximately 92% of the 174 songs that made it into the [Billboard] Top 10 in 2009 contained reproductive messages,” reports Dawn R. Hobbs, SUNY Albany psychology professor and lead author of the study, in Evolutionary Psychology.

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By evaluating whether songs made reference to one or more of 18 different sexually-themed categories, from “genitalia” to “infidelity” to “mate guarding,” the study found that the best-selling songs had “an average of 10.49 sex-related phrases per song”, according to the The Atlantic Wire.

While many musicians face criticism for their provocative song-lyrics — Rihanna’s “S&M” comes to mind — the study offers proof that, musically speaking, sex does sell. (In case you actually still needed proof.)

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