Japan’s male population shrank for the first time on record in the year to March 31, while its total population grew a scant 0.04 percent, the latest sign of the nation’s worsening demographic dilemma.

Experts have said Japan’s falling birth rate means the nation’s population is likely to start shrinking in 2007, fueling concerns about prospects for economic growth.

The number of males totalled 62,076,658 as of March 31, down 0.017 percent from a year earlier, the first such decline since the government began to keep such records in 1968, a government survey published on Tuesday showed.

Japan’s total population, meanwhile, stood at 126,869,397 after posting the lowest rate of increase on record, Kyodo news agency quoted the report as saying.

The decline in the male population was due partly to a rise in the number of men living abroad on business for long periods of time, but natural factors were at work, Kyodo quoted the report as saying.

Japan’s female population, meanwhile, rose 0.09 percent from a year earlier to 64,792,739.

The survey also highlighted the rapid ageing of Japan’s population as well as the falling number of births.

A record low of 1,104,062 births were recorded in the 12-month period, while the percentage of people aged 65 or above rose to 19.72 percent of the total population.

That was a 0.48 percentage point rise from a year earlier.

Japan’s fertility rate - the average number of children a woman bears in her lifetime - hit a postwar low of 1.288 in 2004.

Late marriages and a growing number of people choosing to stay single are often cited to explain the declining fertility rate, along with the high cost of education, crowded housing and long working hours.

The new survey also found that almost half - 49.71 percent - of Japan’s total population now lives in three major urban areas centering on the capital of Tokyo, Osaka in western Japan and Nagoya in central Japan.