Retirement researcher Wade Pfau recently released a paper titled “An Efficient Frontier for Retirement Income” (summary here) in which he compared different allocations of stocks, bonds, fixed lifetime annuities, inflation-adjusted lifetime annuities, and variable annuities with “guaranteed lifetime withdrawal benefit” riders to see how each combination plays out in terms of meeting two competing retirement goals:

Minimizing the shortfall between desired spending and actual spending, and Maximizing the amount of money you leave to your heirs.

The results were rather shocking. So shocking, in fact, that there’s a good chance you’ll read about it elsewhere (which is why I’m hoping to prepare you for what you’ll hear).

What Wade found was that, given the assumptions he used, the ideal allocations for retirees involved only stocks and fixed lifetime annuities. That is, the ideal allocations included no bonds, no inflation-adjusted lifetime annuities, and no variable annuities (although I don’t think many people will find that last part to be particularly shocking).

What’s important to understand, however, is that Wade’s paper is not about showing you how to allocate your money — at least not directly. Rather, it’s about creating a new method for analyzing various allocations — by looking at how well each allocation meets those two goals above, rather than looking at, say, the allocation’s probability of running out of money within 30 years.

The specific results that Wade provides in his paper are only an example of one such analysis. And they use a very specific (though mostly reasonable) set of assumptions (about stock and bond returns, correlations between them, rates of inflation, and so on). When those assumptions are changed, the results might look very different.

In other words, for individual investors, the takeaway is not that you should dump all your bonds in favor of stocks and/or fixed lifetime annuities. Rather, the takeaway is simply that a portfolio completely eschewing bonds in favor of lifetime annuities might not be completely-off-the-wall-crazy. And, given how far such a portfolio would be from conventional retirement recommendations, that’s very interesting.

I hope we’ll see more research along these lines in the near future.