The 90-and-older population nearly tripled in the United States over the past three decades to reach 1.9 million in 2010 and will more than quadruple by 2050, the US Census Bureau said Friday.
Nonagenarians now represent 4.7 percent of the 65-and-older US population, compared to 2.8 percent in 1980. By the middle of the century, they will account for 10 percent of that group, according to the report.
Most Americans aged 90 and over have at least one disability, live alone or in a retirement home and have high school diplomas. And women outnumber men nearly three to one.
The age category is overwhelmingly white (88.1 percent), while blacks accounted for 7.6 percent, Asians 2.2 percent and Hispanics about four percent.
Nonagenarians are also mostly widows and widowers, live in poverty and have more disabilities than those aged less than 90.
"Traditionally, the cutoff age for what is considered the 'oldest old' has been age 85," Census Bureau demographer Wan He said in a statement.
"But increasingly, people are living longer and the older population itself is getting older. Given its rapid growth, the 90-and-older population merits a closer look."
The probability of an elderly person living in a retirement home increases rapidly with age.
While only one percent of those in their late 60s and three percent of septuagenarians live in such facilities, the fraction reaches 20 percent for octogenarians, over 30 percent for nonagenarians and nearly 40 percent for centenarians, according to the Census Bureau.
It said 13 percent more people aged 90-94 have disabilities than those aged 85-89.
