We have made our methods, calculations and software available online at j.mp/SSecurity so that others can replicate or improve our forecasts. The implications of our findings go beyond social science. As the wave of retirement by the baby boomers continues, doing nothing to shore up Social Security’s solvency is irresponsible. If the amount of money coming in through payroll taxes does not increase and if the amount of money going out as benefits remains the same, the trust funds will become insolvent less than 20 years from now.

To save Social Security, which has lifted generations of elderly people out of poverty, tough choices have to be made. One option is to continue raising the retirement age, perhaps to as high as 69 or 70. While the full retirement age is gradually increasing to 67 (for people born in 1960 or later) from 65, this increase is not enough to counterbalance the gains in longevity.

A second option is to increase payroll taxes, for example by taxing wages over $113,700, the current earnings limit. A third is to limit the annual cost-of-living adjustments, possibly by changing how those adjustments are calculated. A fourth is to reduce benefits — for example, by lowering the initial benefits for workers whose lifetime wages are above the national average (currently $43,000 a year). Other choices, in numerous combinations, are possible, too.

One factor that might be considered is new research suggesting that retirement itself, although popular, may reduce life expectancy by breaking lifelong routines and disrupting deep social connections. One might question how much government policy should actively encourage retirement, as opposed to merely making it an option.

Americans need to discuss these difficult choices — and the Social Security Administration needs the ability to improve its forecasting technology by adding statisticians and social science methodologists to help its actuaries institute more formalized quantitative and statistical procedures.

In 1983, after the last time the trust funds ran a deficit, the National Commission on Social Security Reform, led by Alan Greenspan and with members appointed by President Ronald Reagan and Congressional leaders, produced a report that led to changes in payroll taxes. But in the quarter-century since, there have been only modest changes in the program.

We know much more now about mortality and demography, and so an open debate today about Social Security’s future could be even more productive than it was then. The high levels of partisan strife may not make the present seem like the best time to reach a bipartisan agreement. But few issues are more important to more Americans, of both parties, and the longer we ignore the problem, the more disruptive any change will need to be to keep Social Security alive.