Does the “100 Minus Your Age” Investing Rule Still Work? What Wes Moss Thinks

The 100-minus-your-age rule has been handed down through decades of personal finance advice without much scrutiny. The idea is simple: subtract your age from 100, and that number is the % of your portfolio that belongs in stocks. An 85-year-old, by this logic, should hold just 15% in equities. But does this strategy make sense in 2026?

Wes Moss, managing partner and chief investment strategist at Capital Investment Advisors, is also the host of the “Ask An Advisor” segment on The Clark Howard Podcast alongside co-host Christa DiBiase. His verdict on the formula is unambiguous: “It’s a very antiquated, overly crude rule of thumb that I do not subscribe to at all.”

Why the Formula Breaks Down at 80-Something

The 100-minus-your-age rule was built for a world where retirement lasted 10 to 15 years and inflation was manageable background noise. Today, a woman reaching 85 has a meaningful probability of living another decade or more. A portfolio that is 85% bonds and 15% stocks faces a serious inflation problem over that time horizon.

The 2026 Cost-of-Living Adjustment (COLA) came in at 2.8%, up slightly from the 2.5% adjustment in 2025. That figure reflects a persistent upward drift in the cost of services like healthcare. A fixed income stream that covers today’s assisted living costs may well fall short in five years if it does not outpace these rising expenses.

Retirement frameworks are evolving in response. While the traditional 4% rule remains a popular benchmark, Morningstar’s 2026 “State of Retirement Income” research places the safe starting withdrawal rate at 3.9% for new retirees seeking consistent, inflation-adjusted income over a 30-year horizon. Importantly, Morningstar found this rate applies to portfolios holding between 30% and 50% in equities. Portfolios skewed more heavily toward stocks do not support the highest starting withdrawal rates because of sequence-of-return risk. A 15% stock allocation sits far outside that range in the wrong direction, leaving retirees structurally unable to sustain a modern withdrawal plan.

A Multi-Generational Time Horizon Changes Everything

The more powerful concept Moss introduced in a recent episode is one most people managing parental assets never consider: the “family time horizon.” When substantial assets will pass to heirs, the portfolio does not exist solely for an 85-year-old. It belongs, in effect, to the next generation as well.

That mindset shift opens the door to more growth-oriented strategies. Under the SECURE 2.0 Act, workers aged 60 to 63 can take advantage of “super catch-up” contributions to their 401(k) or similar employer-sponsored plan, contributing the greater of $10,000 or 150% of the standard catch-up limit. For 2025 and 2026, the IRS has set that enhanced limit at $11,250, on top of the standard annual deferral. By managing an inherited or family portfolio more like a 55- or 60-year-old would, an affluent octogenarian can position an estate to outpace inflation for beneficiaries.

David from California wrote in to Moss’s show explaining that advisors had recommended moving his mother and mother-in-law toward a 60/40 stock-to-bond split. Despite David’s instinct to be more conservative, Moss agreed with the advisors. With 10-year Treasury yields sitting around 4.55% as of mid-June 2026, driven higher by renewed inflationary pressures, bonds do generate real income. But a 60/40 split also ensures enough capital growth to cover a decade of potential care costs or to leave a meaningful legacy.

The Conversation David Should Have With Those Advisors

Moss recommended talking to the advisors about the actual time and spending needs of both women. That conversation should cover three specific areas.

1. Specific 2026 income: What do care costs total, and how much does Social Security already cover? The maximum benefit for someone who waits until full retirement age in 2026 is $4,152 per month, while those who delay claiming until age 70 can receive up to $5,181 per month, assuming a maximum earnings history.
2. An honest assessment of estate intent: If assets are likely to pass to heirs, the portfolio’s effective time horizon extends well beyond either woman’s life expectancy. That changes the math on appropriate risk-taking considerably.
3. The 3.9% stress test: Run the current portfolio balance against annual withdrawals. Morningstar’s research suggests that a withdrawal rate at or below 3.9% is sustainable for a balanced portfolio over 30 years. If the family’s actual rate clears that bar, a more equity-heavy allocation is generally defensible on the data.

Editor’s note: This article has been updated to correct the maximum Social Security benefit figure for delayed claimants (age 70) to $5,181 per month for 2026, with $4,152 identified as the full-retirement-age maximum. The 10-year Treasury yield has been revised to approximately 4.55% to reflect current mid-June 2026 levels, and the super catch-up contribution limit for workers aged 60 to 63 has been updated to the IRS-confirmed 2026 figure of $11,250. The Morningstar safe withdrawal rate guidance has been corrected to note it applies to portfolios with 30% to 50% in equities, not portfolios requiring a minimum 50% equity allocation.