A new book called Sex By Numbers takes a look at our sexual behaviour using the sexiest medium of all: cold, emotionless numbers.

While the study was made using statistics from the British National Survey of Sexual Attitudes and Lifestyles, the trends and findings may be largely similar as they carry across cultures and countries. While people are becoming more open about their sexual behaviour, it's still something very secretive for most of us, which is why this new study has been getting a lot of attention.

David Spiegelhalter, Professor of Risk at Cambridge University and author of the book, states that the job of the sexologist is made a lot more difficult by the secrecy with which people approach the topic of sex, no matter where they're investigating, but with access to "widest survey of sexual behaviour since the Kinsey Report", he's been able to break down exactly what we're up to in the bedroom, from how long to who with, and when. 

Some of the standout findings include: 

  • 85 kcal - the number of calories burned while doing the deed, which is apparently the equivalent of a few Jaffa cakes
  • 2.7% - the number of men who claim to have successfully self-felated 
  • 9 minutes - the median time from start to finish for a man after vaginal penetration
  • 16 - the median age that people first have sex
  • 80% - the number of people aged 25-35 who say they gave or received oral sex in the last year
  • 3 out of 4 - the number of men living with a partner who say they have masturbated in the last month
  • Oral sex is, in general, practiced by more affluent people with university degrees or higher academic qualifications, while the opposite is true for anal sex

There's plenty more in the study than those few findings, as it looks to "unravel the web of exaggerations, misdirections and downright lies that surround sex in modern society", something which will not only make for interesting reading, but important analysis. 

Via The Telegraph