The older population has been growing for the past 100 years but the decade before 2020 saw its fastest increase since 1880 to 1890.  From 2010 to 2020, the 65-plus population experienced its:

• Largest-ever 10-year numeric gain — an increase of 15.5 million people. The next largest 10-year numeric increase, 5.7 million between 1980 and 1990, was less than half that size.
• Largest-ever percentage-point increase, from 13.0% to 16.8% of the total population. Before 2010, it took 50 years — from 1960 to 2010 — for the older population’s share of the total population to grow by the same number of percentage points.
• Fastest growth rate, 38.6% from 40.3 million to 55.8 million. This was the fastest growth rate of any decade since 1880 to 1890 (40.3%) and more than twice as fast as the previous decade (15.1% from 2000 to 2010). The older population also grew five times faster than the total population, which grew by 7.4%. 

While the older population grew from 2010 to 2020, the size and rate varied for older age groups (Figure 3).

In 2020, the 65-74 age group: 

• Was the largest of the older age groups with 33.1 million people, representing over half of the 65-and-over population.
• Represented 1 in 10 Americans in 2020.
• Experienced the largest growth of any older age group the previous decade. Its numbers grew by 11.4 million or 52.5%, increasing from 21.7 mil­lion in 2010 to 33.1 million in 2020.

Other findings:

• The 75-to-84 age group grew at about half that rate (25.1%) but is expected to pick up the pace in the next decade as baby boomers age into this group.

• The 85-to-94 age group experienced relatively slower growth (12.6%) than other older age groups, increasing from 5.1 million to 5.7 million. 
• The population 95 years and over also expe­rienced a large growth rate (48.6%), increasing from about 425,000 in 2010 to 631,000 in 2020.