Women have long been known to live longer than men, but when it comes to hitting the century mark the difference is stark.
Of the 53,364 Americans age 100 and older, more than 80 percent are women, according to a US Census Bureau report.
The agency's findings, based on data collected from its 2010 census, also found those who make it past 100 are also more likely to be white city-dwellers in the Northeast and Midwest.
According to the Australian Bureau of Statistics, the rates are similar in Australia. There were estimated to be 3049 centenarians in Australia as of March 2012 - 2495 women (82 percent) compared to 554 men.
"Due to sex differences in mortality over the lifespan, the proportion of females in the population increases with age. This is especially true in the oldest ages, where the percentage female increases sharply," Census researchers write.
"For every 100 centenarian females, there were only 20.7 centenarian males," they add.
While reaching 100 years of age may not attract as much fanfare as it did a few decades ago, the public still marvels at those who reach "super centenarian," status.
Guinness World Records, which certifies the oldest living person, said the title was held by Besse Cooper, an American woman who died last week at age 116 in a Georgia nursing home soon after having her hair done.
Guinness announced on its website that the new person to be certified to be the oldest anywhere on the globe is 115-year-old Dina Manfredini, an immigrant from Pievepelago, Italy, who has lived in Des Moines, Iowa, since 1920. She is just 15 days older than Japan's Jiroemon Kimura.
Although still rare, the number of people living past 100 can have an impact as policymakers consider and plan services and programs that affect older adults, the Census says in its report.
Living longer can mean greater medical and retirement expenses, among other issues.
And the number of those living past 100 continues to grow. Just 32,194 Americans reached 100 or older in 1980, far below the current level, according to the Census Bureau. In Australia, there were 363 centenarians at the same time.
Still, centenarians in the United States and Australia remain relatively rare compared to those in other developed countries.
There were 1.73 centenarians per 10,000 people in the United States in 2010 compared to 1.92 per 10,000 people in Sweden, 2.70 per 10,000 in France and 3.43 per 10,000 people in Japan.
In Australia there are 1.37 centenarians per 10,000 people, with the highest rate in the state of South Australia (1.83) and the lowest rate in Queensland of 1.15. The rates in Northern Territory and the ACT are significantly lower due to small population size.