According to a recent study commissioned by the Japanese government, the country’s desire for sex is dropping quickly.

The biennial survey, originally designed to gauge the success of the country’s birth-control education, revealed that 36.1 percent of Japanese males between 16 and 19 had no interest in or even loathed sex. In 2008, that number was 17.5 percent.

Of girls in that 16–19 age group, 59 percent had no interest in sex, up 12 points from 2008.

Forty percent of married people admitted to not having sex within the last month.

Overall, the fertility rate in Japan has dropped to 1.37 births per woman. It’s 2.06 in the U.S. Such a low rate, if it continues, could have major consequences for the Japanese economy.

All age categories, other than men 30 to 34, reported a general indifference toward sex, compared to the responses from two years ago.

Why such a drop in sexual desire?

The plight of the young Japanese man with no sexual desire has been covered before. They’re known as “grass-eating boys” or “herbivores.” They’re young men with no real interest in sex, a relationship, a career, or most material things. A convergence of two of the country’s biggest problems: the fledgling birth rate and the drop in consumption.

Alexandra Harney wrote about “The Herbivore’s Dilemma” for Slate in June of 2009:

Grass-eating boys’ commitment phobia is not the only thing that’s worrying Japanese women. Unlike earlier generations of Japanese men, they prefer not to make the first move, they like to split the bill, and they’re not particularly motivated by sex. “I spent the night at one guy’s house, and nothing happened—we just went to sleep!” moaned one incredulous woman on a TV program devoted to herbivores. “It’s like something’s missing with them,” said Yoko Yatsu, a 34-year-old housewife, in an interview. “If they were more normal, they’d be more interested in women. They’d at least want to talk to women.” Don’t like ads? Become a supporter and enjoy The Good Men Project ad free

The herbivores have rejected just about every traditional definition of masculinity. The growing role of women in professional Japan, along with fewer guaranteed-salary positions—formerly a staple of Japanese culture—led to the rise of the herbivore, according to Harney.

At the same time, the increased role of women in Japanese society might be hurting the sex drive of those same women. It’s still a widely held belief in Japan that women should quit their jobs once they give birth. So, they’re rejecting sex and marriage in the interest of a prolonged, more successful career.

As I mentioned, once Japanese men and women get married, their sexual desire doesn’t seem to increase either. For the couples that weren’t having frequent sex, reasons cited were a “vague reluctance after childbirth, that they could not be bothered, or that they were too tired after work.”

If no one’s having sex, Japan’s birthrate can’t increase. And it needs to: the country’s population dropped by a record number in 2010.

What do you think of Japan’s countrywide lack of a sex drive? What about the herbivores? How can Japan right the ship? Let us know.

—Photo mecredis/Flickr

[MORE STORIES FROM GOOD FEED]