We take a look at some of the most bizarre sex surveys ever.
Sex makes you smarter
It seems that whatever you need to achieve the best results somewhere quiet you can concentrate on the task at hand, an early start before work colleagues arrive, or just an uninterrupted routine most men do a better, more accurate job when they're thinking about sex.
Researchers at the University of Amsterdam found that hormones released during sex (or when thinking about sex) enable us to concentrate better while performing challenging mental tasks. As a result, subjects' test scores were higher for those who were thinking about sex than for the ones thinking about almost anything else.
Paint that bedroom
A new survey from home UK retailer Littlewoods suggests men with purple bedrooms have sex more than the rest of us. A study of more than 2,000 adults revealed that couples choosing purple decor averaged 3.5 lovemaking sessions a week, compared with 3.2 for those who chose red and just 1.8 for couples favouring grey.
The company's style expert Laurence Llewelyn-Bowen noted that a beige bedroom usually means a beige sex life, although it seems changing your bed linen can help. Apparently couples who sleep between silk sheets make love on average 4.25 times a week, nearly twice as often as those who prefer nylon or polyester.
Playing footsie on the FTSE
Sales of sex toys frequently peak when the economy slumps, and dramatic increases in infidelity have been observed during recessions. Scientists at the University of Kansas think the rise in sexual activity during economic downturns may be explained by a search for relatively 'affordable entertainment' but only partly.
The other reason could be evolutionary. Men are programmed to reproduce, say the researchers, and when faced with a 'threatening environment' our hard-wired drive to seek short-term mating strategies might be designed to ensure that even if we perish our genes will live on.
Still waters run weird
The results of a survey 20 years ago into the sex lives of 5,000 librarians were buried at the time and the researcher fired because they were considered so scandalous. But in fact, now a copy has surfaced, most of the findings are just plain bizarre rather than disturbing or criminal.
Nearly 40 per cent of female librarians, for example, said they'd sleep with the fictional character Pee-wee Herman if he was the last man on the planet, and presented with a list of celebrities and asked which one they'd like to marry, 60 per cent chose Robert Redford, 18 per cent Patrick Swayze and 3 per cent Cher.
Does disco make you gay?
It's true research results cannot always be extrapolated from one species to another but it's hard to ignore the implications of a 1984 study which found that 'high level noise, such as that frequently found in discos, causes homosexuality in mice.'
Pigs remain relatively unaffected by the same music, apparently, except that eventually they go deaf. But rival scientists have found that another way to get male mice to lose interest in females is to feed them cannabis, or castrate them.
Too lazy to score
When a web survey discovered that 65 per cent of Brits would like more sex than they're presently getting, researchers asked what was stopping them. For almost a fifth it was lack of a long-term partner, which makes sense, and 2.2 per cent said the cause was financial.
Nearly a third of respondents blamed it on a lack of energy, however, while a further quarter said they didn't have the time. In any other context that sounds like people who just can't be bothered, the sort who'd sooner find an excuse than an answer.
X-rating versus Z-count
A report from the US earlier this year indicated that six out of 10 adults preferred a good night's sleep to sex. For women the figure was even higher (at 79 per cent) although it's probably worth noting that the survey was carried out on behalf of a consortium of mattress manufacturers.
Mind you, not so long ago 86 per cent of American respondents said they'd sooner drive a new Range Rover than date Claudia Schiffer, while in another survey 65 per cent of them admitted they would sooner give up sex than have to stop driving.
Keeping a stiff...upper lip
In 2011 condom manufacturer Durex surveyed some 26,000 residents in more than two dozen countries. The results showed Britons to be near the bottom of world rankings in terms of how often we have sex, and how much satisfaction we derive from doing it.
Surprisingly, given all its other problems, Greece topped the results table, with Brazilians and Russians not far behind. Bumping along the bottom with us were the United States, Canada and Japan, where just 15 per cent of respondents said they were satisfied with their love lives.
Oral sex: the all-purpose pick-up
We're guessing the research was led by a guy, but a survey of 300 women at the State University of New York (Albany) seems to indicate that oral sex could have amazing healing powers, or at least provide an alternative to chemical antidepressents.
Researchers found the women who indulged their partners were happier than those who did not, the report noting: 'Semen is known to contain such mood-altering chemicals as estrone and oxytocin, which elevate mood; cortisol, which promotes affection; serotonin, which acts as an antidepressant; and melatonin, which induces sleep.'
How long is too long?
When a leading women's mag (Glamour) asked 1,000 men how long they'd like to keep going for ignoring their partner's feelings for the purposes of the survey, and excluding time spent on foreplay the results made surprising reading.
More than half said they'd be happy with somewhere between 15 minutes and half an hour. But 30 of those surveyed admitted that for them less than five minutes was just fine, while more than a fifth of respondents said they'd definitely like to be at it for an hour.