While the U.S. has large numbers of aging baby boomers, many countries are aging even faster. In these countries, a significant portion of the population is already age 65 or older, and more than 20 percent of people are expected to become senior citizens by 2030, according to Census Bureau data.
Japan is home to some of the oldest citizens in the world. A quarter of Japan's population (25.8 percent) is age 65 or older in 2014, and nearly a third (32.2 percent) of Japanese people are expected to be senior citizens by 2030.
Germany has 17 million people who are age 65 and older, but that number is expected to swell to 21 million by 2030. Senior citizens are projected to make up 27.9 percent of the population in 2030, up from 21.1 percent today.
The nearly 13.1 million senior citizens in Italy make up 21 percent of the country's population. By 2030, there are projected to be nearly 16 million retirees, and over a quarter (25.5 percent) of Italian citizens will be age 65 or older.
There are already 12 million senior citizens in France, and they make up 18.3 percent of the population. By 2030, their ranks are projected to increase to 16 million and make up 23.4 percent of the French population.
There are 8.4 million Spanish senior citizens, and they comprise 17.6 percent of Spain's population. Those numbers are expected to grow to 11.5 million people age 65 and older in 2030, when senior citizens will make up 22 percent of the population.
The United Kingdom has 11 million people age 65 and older, who make up 17.5 percent of the country's population. The number of senior citizens is projected to grow to 14.6 million by 2030, when they will make up 21.3 percent of the UK's residents.
Some 17.3 percent of Canadian citizens are age 65 or older, a proportion that is expected to grow to nearly a quarter (24.9 percent) by 2030. At that time, there are projected to be nearly 9.6 million Canadian senior citizens, up from 6 million today.
In Ukraine, 15.9 percent of people are age 65 or older, a proportion that is expected to grow to 22 percent by 2030. The number of senior citizens is expected to climb from 7 million in 2014 to 8.7 million in 2030.
The number of retirees in Poland is expected to increase from 5.7 million in 2014 to 8.5 million in 2030. At that time, people age 65 and older will make up 23.1 percent of the population, compared with 15 percent today.
The U.S. will have a slightly smaller proportion of senior citizens than many other developed countries, growing from 14.5 percent in 2014 to 20.3 percent in 2030. However, the number of retirees is significantly larger and is expected to jump from 46 million in 2014 to a staggering 72.8 million by 2030.
Russia is slightly younger that the U.S., with the proportion of senior citizens expected to grow from 13.3 percent in 2014 to 20.1 percent in 2030. In China, retirees make up just 9.6 percent of the population, which is expected to increase to 17.2 percent by 2030. And in India, where only 5.8 percent of people are senior citizens, just 8.8 percent of the population will be 65 or older in 2030.
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