New official data revealed that for the first time, over 10% of the Japanese population has reached the age of 80 or older, highlighting the ongoing challenge of an increasingly aging population in the country.

Government data released on Sunday, ahead of Monday's "Respect for Aged Day" national holiday, also showed that the share of Japan's population at 65 or older expanded to a record 29.1% from 29.0% a year ago.

The level compared with second-ranked Italy's 24.5% and third-ranked Finland's 23.6%, according to the Ministry of Internal Affairs and Communications.

"Japan has the highest percentage of elderly population in the world," the ministry said in a press release.

For decades, Japan has seen its population shrink and grow older as young people delay marriage and children, largely due to unstable jobs and economic difficulties.

As a result, Japan has seen ballooning costs for elderly care, with not enough young people to fill jobs and pay for various social and welfare programs.

The ministry said that with the baby boomer population turning 75 or older, Japan's 124.4 million people are continuing to grow older.

Around 12.59 million people are 80 or older, while 20 million are 75 or older, it said.

As a result, Japan is relying on an elderly labor force.

More than 9 million elderly are working, accounting for 13.6% of the workforce, or one in seven workers in Japan.

A quarter of all elderly in Japan have jobs, less than South Korea's 36.2%, but far ahead of other developing countries such as the United States at 18.6% and France at 3.9%.

More than a third of people between 70 to 74 have jobs in Japan, the data showed.

By 2040, Japan's elderly population is projected to account for 34.8% of the population.