Japan's citizens are living longer than ever, with 40,399 now age 100 or older, the Associated Press reported. Eighty-six percent are women.
The country's gray population is accelerating rapidly, and by 2050, Japan's over-100 residents will approach 1 million, the U.N. predicts.
Concerns about its strained public pension and health care systems have led the government to begin extending the retirement age to 65 from 60. Some are urging it go to 70, the AP said.
"The data clearly show that Japan is aging rapidly and steadily, mainly because of progress in medical care and the high living standard since the end of World War II," Health and Welfare Ministry official Hiroyuki Ishii said in a statement honoring the elderly.
Life expectancy in Japan is among the longest in the world -- 86 years for women and 79 years for men.
The nation's centenarian population has soared from 10,000 only 10 years ago, to 30,000 in 2007, and another 10,000 since then, the ministry said.