It also points out "the need to inform individuals and educate policymakers about the decumulation phase of retirement, when people are spending down their retirement assets."

The paper identifies five challenges of longevity risk:

1. Accumulating adequate savings during one's working life.

2. Having adequate information on saving and managing savings, both before and during retirement.

3. The need for flexible regulations to accommodate different retirement needs.

4. Agreement that decumulation is fair and that governments and regulators understand just what "fair" is.

5. Agreement that changes within the retirement market should develop a long-term sustainable market.

The question of longevity is itself something of an enigma. New mortality tables adopted in 2014 have resulted in the funded levels of defined benefit retirement plans falling substantially (aided, of course, by market activity).

Updates to those tables released earlier this month have offered the potential for some relief for plan sponsors, since their assessment of longer-lived Americans is not quite so aggressive as the 2014 tables' calculations.

The release of the updates, which still show longer lifespans but not as long as indicated in the 2014 data, was cause for celebration, but also for debate: Officials and sponsors have not agreed on whether, and how strictly, to implement the new standards.

Even actuaries have weighed in, with the American Academy of Actuaries (the one collaborating on the paper) disagreeing with how the Society of Actuaries (the ones issuing the 2014 standards) reached their conclusions.

As the argument raged on, the Department of the Treasury delayed implementation of the 2014 tables, and that was followed by the release of the updated tables.

SOA is currently seeking additional sources of mortality data from the Center for Disease Control and the Centers for Medicare and Medicaid to ensure that its modeling is the best possible.