In actuality, the life expectancy at age 65 has increased to the extent that Social Security is paying out more benefits for a grand total of 3 years, after 70 years in operation. This is why the system endures, with minor changes (the retirement age has already increased to 67), because the people who designed it built in the flexibility and buildup of benefits in the trust fund to account for any population pattern shifts. About the only thing they didn’t expect was the massive, rampant inequality that made the payroll tax cap lead to a far lower collection in revenues than expected. That can be altered and the program saved with relative ease.