In a move that proves the validity of the scientific method now and forever, researchers have developed a math formula defining the perfect butt.
According to a study published in the journal of Plastic and Reconstructive Surgery, the formula is actually a lot simpler than most equations to be born from science. It’s just a single number: 0.7.
That’s the ratio of how large a woman’s waist should be in comparison to their hips. To put it into cooking terminology, the ideal feminine behind is 7 parts waist to 10 parts hips.
There are many examples of classic Hollywood stars who possessed this figure, like Marilyn Monroe, Sophia Loren, and Elizabeth Taylor. Modern pop stars are also known to have the magic figure, such as Beyonce Knowles-Carter (although her recent pregnancy may have skewed the numbers some) and Kate Winslet.
The study was performed by surveying 583 plastic surgeons and 450 members of the public on their opinion of female body shapes. They were each given a series of photographs of a single model digitally altered so she had varying hips to waist ratio. 39% of respondents picked the photograph with the ratio of 0.7 as their ideal female form.
Conducted with respondents from all over the world, the survey found that each region had their own variation on the ideal. Unsurprisingly, Latin America preferred their women a little more bottom heavy (a number closer to 0.6), followed by Asia and North America. Europe preferred their women to be the least curvy.
This magic ratio is actually not new to modern behavioral science. A similar study was performed in 2010 by Dr. Barnaby Dixson, an anthropologist in New Zealand, which also gave altered photographs to male respondents in a survey. That study also concluded the most popular ratio was 0.7 and was published in the Archives of Sexual Behaviour.
Elizabeth Cashdan of Utah University did similar work by studying Playboy centerfolds. After taking measurements from hundreds of magazines she found the ideal ratio to be a little lower at 0.68.
Doctors have been increasingly recommending the waist to hips ratio is a better determinant of health than BMI, and multiple studies have confirmed that a slim waist with wider hips is associated with positive health outcomes.
Perhaps proving there is still sexism in the field, there is no word yet on an ideal male butt ratio.