From the perspective of economics and life cycle finance, the immediate annuity is often viewed as the perfect retirement vehicle; in research dating back to Yaari (1965), it has been shown that for someone whose primary concern is outliving his/her money (as opposed to leaving a bequest to future generations), investment dollars should be annuitized to generate a superior return over bonds (due to mortality credits) while protecting against mortality risk.
Yet economists have long struggled to explain the so-called "annuity puzzle" - the fact that while the research suggests annuitization should be optimal, in practice remarkably few people ever choose to do so. Does that mean they're all just being driven by an irrational decision-making process and just need to be better educated to understand the true benefits of immediate annuities, or is there some other factor at play?
In new research, researchers Felix Reichling of the Congressional Budget Office and Kent Smetters of the Wharton School of Business think they have found a new way to explain the puzzle: the fact that the value of an immediate annuity changes over time due to incremental (and sometimes shocking) changes in health and mortality. In fact, it can be the worst of both worlds - severe health events can simultaneously reduce life expectancy (decreasing the remaining value of the annuity) and increase cash flow needs (to pay for the necessary care). And when viewed in this dynamic context, the value of annuitization can be quite risky indeed; so much, in fact, that Reichling and Smetters find that for those who are relatively risk averse and/or have limited retirement assets, that the most rational annuity allocation might be to avoid them altogether, and the ideal might even be for many to have negative exposure and "short" annuities instead!