[nybble41]

In 1945 there were 42 workers paying SS taxes for every retiree collecting benefits. For equal pay / retirement income after SS taxes, each worker only needs to provide 2.3%.

Today (actually since 2009) that ratio is three workers per retiree. Each worker has to provide 33%. By 2050 the ratio is projected to fall to two-to-one.

You can find the historical ratios here: https://www.ssa.gov/history/ratios.html

[0des]

Did we get more people not working and paying taxes, or did we get more people consuming this resource? If it is the latter, how'd that happen?

[nybble41]

Mostly people are living longer. When SS first started only 55% of males and 60% of females who made it to age 21 would have survived their working-age years to retire at age 65 in 1940. By 1990 that figure had risen to 72% and 83%, respectively. Life expectancy after retirement also increased, from 12.7 (M) or 14.7 (F) years in 1940 to 15.3 or 19.6 years in 1990. (https://www.ssa.gov/history/lifeexpect.html)