摘要:The U.S. public pension system, known as Social Security, has a big problem. Within the next 15 years, it is expected to use up all its fi nancial reserves. The looming revenue shortfall is hardly surprising. In fact, it has been predicted for more than a quarter of a century. A combination of below-replacement birth rates and rising longevity is boosting the share of Americans who have reached the pensionable age. Under current law, when Social Security reserves are depleted, monthly benefi ts will have to be fi nanced solely by the dedicated payroll and income tax rev- enues fl owing into the system. The Social Security actuary expects that in 2035 these dedicated revenues will cover just 80% of the pension payments promised under today’s benefi t formula. In other words, if future Congresses and Presidents do not change the law, pensioners’ monthly benefi ts will have to be cut one-fi fth in the next 15 years. One implication of this forecast is that workers who fi le claims for Social Security today can plausibly expect to see their monthly pen- sions cut before they reach advanced old age.