America's older population - 65 and above - will reach 83.7 million in the year 2050, almost double in size from the 2012 level of 43.1 million, according to two US Census Bureau reports released today.
A large part of this growth is due to the ageing of baby boomers (individuals born in the US between mid-1946 and mid-1964), who began turning 65 in 2011 and are now driving growth at the older ages of the population, the report said.
"The United States is projected to age significantly over this period, with 20 per cent of its population age 65 and over by 2030," said Jennifer Ortman, chief of the Census Bureau's Population Projections Branch.
"Changes in the age structure of the US population will have implications for healthcare services and providers, national and local policymakers, and businesses seeking to anticipate the influence that this population may have on their services, family structure and the American landscape," Ortman said.
Although the older population is not as racially and ethnically diverse as the younger population, it is projected to experience a substantial increase in diversity over the next four decades, the report said.
The 65-and-older population is projected to be 39.1 per cent minority in 2050, up from 20.7 per cent in 2012, while the 85-and-older population is projected to be 29.7 per cent minority in 2050, up from 16.3 per cent in 2012.
In 2012, there were 22 people 65 and older for every 100 working-age people in the US. By comparison, in 2030, there will be 35 people 65 and older for every 100 working-age people.
This means there will be approximately three working-age people for every person 65 and older, the report said.
After 2030, the number of people 65 and older for every 100 working-age people in the US continues to increase slightly to 36 by 2050.
The proportion of the total population 65 and older is projected to increase in all developed countries between 2012 and 2030, it added.
Although the US is projected to age over this period, it will remain one of the younger developed countries with only 20 per cent of its population 65 and over in 2030, the report said.
The majority of the growth in the 65-and-older population is projected to occur between 2012 and 2030 as the baby boomers enter the older age group.
When the first of the baby boomers turned 65 in 2011, there were just under 77 million people in the baby boom ages.
"The baby boom population is projected to drop to 60 million by 2030 and to only 2.4 million by 2060. By 2060, the youngest baby boomers will be 96 years old. In 2012, baby boomers comprised 24.3 per cent of the US population.
"As baby boomers age, their share of the population is projected to decrease to 16.7 per cent in 2030 and 3.9 per cent in 2050," the report said.