Policymakers have designed Social Security to be a progressive retirement program that replaces a larger share of monthly earnings for low- and middle-income workers than for high earners. However, previous research has found that, although the Dis-ability Insurance (DI) component of Social Security is very progressive, the Old-Age and Survivors Insur-ance (OASI) component may be less progressive than intended. One reason is that high earners tend to live longer than low earners. Since Social Security pays an annuity that lasts throughout retirement, it benefits high earners with greater longevity.