Asset allocation is how you divide your portfolio among stocks, bonds, and cash, and it is the biggest single driver of your long-term results and volatility. A common approach ties that mix loosely to your age, holding more stocks when you are young and more bonds as retirement nears. This guide explains the logic and the popular rules of thumb.
Why time horizon drives the mix
The longer you have until you need the money, the more short-term volatility you can afford to ride out. A 30-year-old has decades for markets to recover from downturns, so a stock-heavy portfolio makes sense. Someone retiring in five years has far less time to recover, so they typically hold more bonds for stability. Time horizon, not age itself, is the real driver, and the two just tend to move together.
Popular rules of thumb
A classic guideline is to subtract your age from 110 or 120 to get your target stock percentage. Under the 110 rule, a 30-year-old holds about 80% stocks and a 60-year-old about 50%. These formulas are starting points, not laws, and many investors adjust for their own risk tolerance and savings. The rules simply encode the idea of gradually dialing down risk over time.
The glide path and target-date funds
The gradual shift from stocks toward bonds as you age is called a glide path. Target-date funds automate it, so you pick the fund with a year near your retirement and it slowly grows more conservative on its own. This hands-off approach keeps most people appropriately allocated without any manual rebalancing. The trade-off is less control and a one-size-fits-all path.
Adjusting for your situation
Age is only one input, because your risk tolerance, job stability, other income, and goals all matter. A pension or Social Security acts a bit like a bond, which may let you hold more stocks elsewhere. Someone who panics in downturns should hold more bonds than a formula suggests, since the best allocation is one you can actually stick with. Revisit your mix every few years or after big life changes.
Using the 110-minus-age rule, a 35-year-old would target about 75% stocks and 25% bonds, while a 65-year-old would target about 45% stocks and 55% bonds. A single target-date fund can hold that mix and rebalance it automatically as the years pass.
Key takeaways
- Asset allocation, your stock, bond, and cash mix, drives most of your risk and return.
- Longer time horizons justify holding more stocks.
- Rules like 110 or 120 minus your age give a rough stock target.
- Target-date funds automate the shift toward bonds via a glide path.
- Personal risk tolerance and other income should adjust any formula.
Common mistakes
- Staying nearly all-stock right up to retirement with no cushion for a downturn.
- Going too conservative while young and missing decades of growth.
- Setting an allocation once and never revisiting it as your life changes.
FAQ
Is the 110-minus-age rule right for everyone?
No. It is only a starting point, and your risk tolerance, other income, and goals can justify holding more or fewer stocks.
What is a glide path?
It is the preset schedule by which a portfolio, often a target-date fund, gradually shifts from stocks toward bonds as retirement approaches.