Final answer:
Social Security is the largest source of income for Americans over the age of 65. It supports the majority of the retired population and many rely on it exclusively. As the elderly population grows, the program's sustainability is an increasing concern.
Step-by-step explanation:
The largest source of income for people over the age of 65 in the United States today is Social Security. Social Security provides benefits to over 48 million Americans and is a critical component of economic survival for the elderly. For a significant portion of the retired population, it is their only source of income, with somewhere between 12 percent and 40 percent of retirees relying solely on these benefits according to varying expert opinions.
The importance of Social Security increases as retirees age, especially after the age of 85, as their savings deplete and health care costs rise. Despite Social Security never being intended to fully replace other forms of income, providing benefits equivalent to around 42% of an individual's previous wages, it remains the most significant income source for the majority of elderly Americans, with lower-income earners receiving benefits that represent a higher share of their earnings.
As the proportion of elderly Americans increases, so too will reliance on Social Security. The program's sustainability is a matter of concern, as current funding through payroll taxes may not cover the expected increases in costs due to an aging population.