COMPANIES have been urged to give their employees more time off to procreate; shops have offered discounts for larger families; and the government has introduced child allowances to lift the birthrate. Yet try as it may, Japan appears unable to stop its inexorable slide into long-term population decline.

With the global population forecast to reach nine billion by the middle of the decade, Japan is bucking the trend. Instead, its low birthrate and ageing society are taking the world's third-biggest economy to the brink of a demographic crisis to which it is struggling to find solutions.

The traditional pyramid population model is beginning to flip upside down against a backdrop of fewer, and later, marriages, while life expectancy continues to rise thanks to a traditional low-fat diet and advanced medical treatments paid for by universal health insurance.

Demographers warn that if current trends continue, Japan's population will look much smaller and greyer in just a few decades. Although the population increased slightly last year to just over 128 million, according to government figures, the most recent census attributes the rise to more people returning to Japan than had left.

The long-term trend points to an accelerated decline. The current population will dip below 100 million in 2046, according to the National Institute of Population and Social Security Research in Tokyo, before sinking to below 45 million in 2105.

For many Japanese, having sexual relations appears to be low on the agenda: a 2008 survey found that the average Japanese couple had sexual relations 45 times a year, less than half the global average of 103 times.

The birthrate, at 1.34 — the average number of children a woman is expected to have during her child-bearing years — is below the 2.1 experts say is necessary to keep the population stable.

“Even that is a conservative estimate,” says Futoshi Ishii, a researcher in population dynamics at the institute, who adds that it is too early to gauge the impact on the birth rate of the recent introduction of allowances for children up to the age of 15.

Local authorities and the private sector have attempted to encourage couples to have more children, from offering shopping vouchers to larger families to launching officially sanctioned matchmaking websites.

The country's biggest business lobby, Keidanren, has encouraged its 1,600 member firms to allow employees to spend more time with their spouses and, so the theory goes, have more children. — The Guardian, London