The traditional ideal of retirement income is the three-legged stool of Social Security, employer-provided retirement plan, and personal savings.
This ideal is not widely achieved, in part because employer-provided plans are not universal and in part because many retirees have little or no income from savings. In fact, earnings from work were slightly higher than income from assets or employer benefits in 1998.
Social Security was the largest source of retirement income, accounting for 37.6 percent of income in 1998 for those aged 65 and older, on average. Earnings accounted for 20.7 percent, income from assets 19.9 percent, and employer benefits 18.7 percent.
Read more about retirement issues in "Changing retirement age: ups and downs," by William J. Wiatrowski, Monthly Labor Review, April 2001. The income data for that Monthly Labor Review article were obtained from the Social Security Administration.
Bureau of Labor Statistics, U.S. Department of Labor, The Economics Daily, Sources of retirement income at https://www.bls.gov/opub/ted/2001/may/wk3/art03.htm (visited December 08, 2022).