YOKOSUKA (Japan) • Ever since her elderly neighbour moved away a decade ago, Ms Yoriko Haneda has done what she could to keep the empty house from becoming an eyesore. She regularly trims its shrubs, maintaining a perfect view of the sea.
The volunteer yard work has not extended to the house two doors down, however. That one is vacant, too, and overgrown with bamboo. In fact, dozens of houses in this neighbourhood are abandoned.
"There are empty houses everywhere, with more cropping up all the time," said Ms Haneda, 77, complaining that thieves had broken into her neighbour's house twice.
Despite a deeply rooted national aversion to waste, discarded homes are spreading across Japan. Long-term vacancy rates have climbed significantly higher than in the United States or Europe, and some eight million dwellings are now unoccupied, according to a government count.
Nearly half of them have been forsaken completely. These ghost homes are the most visible signs of human retreat, in a country where the population peaked a half-decade ago, and is forecast to fall by a third over the next 50 years.
"Their kids are in modern high-rises in central Tokyo. To them, the family home is a burden, not an asset."
MR TOMOHIKO MAKINO, a real estate expert, on the rising number of abandoned houses in Japan
The demographic pressure has weighed on the Japanese economy, as a smaller workforce struggles to support a growing proportion of the aged, and has prompted debate over long-term proposals to boost immigration, or encourage women to have more children.
After decades of struggling with overcrowding, Japan is confronting the opposite problem: When a society shrinks, what should be done with the buildings it no longer needs?
Many of Japan's vacant houses have been inherited by people who have no use for them, and yet are unable to sell them off because of a shortage of interested buyers.
The government passed a law this year to promote demolition of the most dilapidated homes. But owners can be hard to track down, and are often reluctant to pay demolition costs.
Once limited mostly to remote rural communities, the phenomenon is now spreading through regional cities and the suburbs of major metropolises.
Yokosuka, for one, is located within commuting distance of Tokyo. Close to naval bases and automobile factories, it attracted thousands of young job-seekers in the era of roaring economic growth after World War II. But the young workers of the post-war years are now retirees.
"Their kids are in modern high-rises in central Tokyo," said Mr Tomohiko Makino, a real estate agent. "To them, the family home is a burden, not an asset."
Japan's birth rate has been stuck below the level needed to maintain the population since the 1970s, as young people delay marriage, and many women put off having children as they enter the workforce.
The city of Yokosuka is trying to change that, by encouraging owners of abandoned houses to put them on the market. It has established an online "vacant home bank" to showcase houses that commercial real estate agents will not touch.
But Mr Hidetaka Yoneyama, a housing specialist at the Fujitsu Research Institute, a think-tank, says developers are still building more than 800,000 new homes and condominiums a year in Japan.
In 20 years, he calculates, more than one-quarter of Japanese houses could be empty.
NEW YORK TIMES