Sequence-of-Returns Risk: Why Your Retirement Date Matters More Than Your Return

Average annual return is the number most people focus on when planning retirement withdrawals. It's also, on its own, a poor predictor of how a retirement portfolio actually behaves — because when the good and bad years happen matters as much as how many of each there are.

The same average, two different outcomes

Imagine two retirees, each starting with an identical portfolio and each experiencing the exact same set of annual returns over a 25-year retirement — just in reverse order from one another. Both end up with the same average return. But the retiree who experiences a market decline in the first few years of retirement, while also withdrawing income, sees their portfolio shrink from two directions at once: the loss itself, and the withdrawals coming out of a smaller base. There's less money left to participate when the market eventually recovers.

The retiree who happens to experience strong returns first builds a larger cushion before any decline arrives, and can typically weather the same eventual bad years far more comfortably — again, despite an identical long-run average return.

This is sequence-of-returns risk: the danger isn't a bad average, it's bad timing, concentrated in the years immediately around when withdrawals begin.

Why this is the real risk behind the "4% rule"

The well-known 4%, and more recently closer to 3.9%, "safe withdrawal rate" guidance comes from historical research into exactly this problem — testing withdrawal rates against every historical sequence of real market returns, not just the long-term average, to find a rate that survived even the worst-timed retirements in the historical record. The rate is deliberately conservative because sequence risk, not average return, is what has broken retirement plans historically.

What actually helps

A few practical responses show up repeatedly in retirement-income planning: holding one to two years of spending in cash or short-term bonds so a market decline doesn't force you to sell depressed stock holdings for income; staying flexible on withdrawal amounts in years immediately following a downturn rather than withdrawing a fixed amount regardless of performance; and, for some households, using guaranteed income sources (like delaying Social Security, or an annuity) to cover essential expenses so portfolio withdrawals can flex with the market.

None of this changes your long-run average return. It changes how much of a bad sequence you can survive without being forced to sell at the worst possible time — which, historically, has mattered more.