The number of children under the age of 15 in Japan has fallen to a record low
As of 1 April, there were 17.38 million children aged 14 or below in the country - down 140,000 from last year.
This is the 26th straight year of decline in numbers of under-15s, the internal affairs ministry said.
Japan has the world's highest ratio of elderly to young people, raising serious concerns about future economic growth and the funding of pensions.
The interior ministry released its population estimates a day before the Children's Day national holiday in Japan.
According to the figures, the number of children aged under 15 makes up just 13.6% of Japan's population - a record low.
That figure is estimated to fall to 12.3% - roughly half that of the elderly population - by 2015.
In 2005, Japan's population declined for the first time since World War II.
A government survey at the end of last year predicted that the dwindling birth rate would cut Japan's population by 30% in the next 50 years - from the current level of 127 million to below 90 million.
Correspondents say the current trend is caused by women marrying later in life and having fewer children.
The Japanese government has pledged to bring in policies to make it easier for women to have children, by improving child care and maternity rights for working women.
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