Final answer:
The United States had approximately 80,000 centenarians in 2010, with projections suggesting there could be half a million by 2050. This is part of a broader trend of an aging population, with global numbers of those aged 65 and over expected to double to 1.5 billion by 2050.
Step-by-step explanation:
As of 2010, there were approximately 80,000 centenarians in the United States. Given the aging population trend, the U.S. Census Bureau projects that by the year 2050, the number of Americans aged 100 or older could reach half a million. This expected increase is reflective of a larger demographic pattern where the elderly population (those 65 and older) is projected to double from 703 million in 2019 to 1.5 billion by 2050 globally, representing one in six people worldwide.
Life expectancy has been a significant factor contributing to the rise in the elderly population; in the United States, the life expectancy is on average 79 years. Furthermore, the U.S. population itself is changing, with shifts towards a higher percentage of the population being of Hispanic origin, driven by differences in fertility rates and immigration.
Centenarians are a quickly growing segment within the elderly demographic, and their increasing numbers will have notable implications for healthcare, social security, and other policy areas. The U.S. and other nations will continue to face the challenges and opportunities associated with an aging populace.