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, the Atlanta-based retirement planner and host of the “Ask An Advisor” segment on The Clark Howard Podcast, has a direct verdict on that formula: “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.

While inflation has cooled from pandemic highs, the **2026 Cost-of-Living Adjustment (COLA) was finalized at 2.8%**. While this is lower than recent years, it reflects a persistent upward drift in the cost of services like healthcare. A fixed income stream that covers today’s assisted living costs may fall short in five years if it doesn’t outpace these rising costs.

In a recent podcast episode, Moss discussed how retirement frameworks are evolving. While the traditional 4% rule remains a popular benchmark, many researchers in 2026 now point to a **3.9% safe withdrawal rate** as the more prudent baseline for the 2026-2028 “risky period.” Moss notes that this math is predicated on holding at least 50% in stocks. A 15% stock allocation is not just conservative; it is structurally incompatible with the withdrawal math required to sustain a modern retirement.

A Multi-Generational Time Horizon Changes Everything

The more powerful concept Moss introduced is one most people managing parental assets never consider: the “family time horizon.” If substantial assets will pass to heirs, the portfolio isn’t just for an 85-year-old—it’s for the next generation.

This mindset shift allows retirees to take advantage of current tax-efficient growth strategies. For example, under the **SECURE 2.0 Act**, workers aged 60 to 63 can now utilize **”Super Catch-up” contributions**—contributing the greater of $10,000 or 150% of the standard catch-up limit. By investing more like a 55 or 60-year-old, an affluent octogenarian can ensure their estate outpaces inflation for their 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 near 4.3%, bonds offer real income, but a 60-40 split ensures the capital growth necessary to cover a decade of potential care or a substantial 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. This discussion might include:

1. Specific 2026 Income: What do care costs total, and how much does the updated Social Security benefit—which can reach a maximum of **$4,152** for delayed claimants in 2026—already cover?
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.
3. The 3.9% Stress Test: Run the current portfolio balance against annual withdrawals. If the withdrawal rate is at or below the 3.9% baseline, a more aggressive equity allocation is generally sustainable.