This is a slightly tricky question.
There were a lot of infant deaths in the early 1900s and this contributed to the recorded "life expectancy" rates of the era: 58 for men and 62 for women. "...the majority of Americans who made it to adulthood could expect to live to 65, and those who did live to 65 could look forward to collecting benefits for many years into the future. [...] Almost 54% of the them could expect to live to age 65 if they survived to age 21, and men who attained age 65 could expect to collect Social Security benefits for almost 13 years (and the numbers are even higher for women)."
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