Ask what drives investment results and the answer is not stock picking or market timing, it is asset allocation: how you split your money between stocks, which grow but swing, and bonds, which steady the ride but grow slowly. That single decision explains most of your long-run return and risk, and the right mix changes as you move through life.
Here is how to think about it by age, and why your own timeline beats any formula.
Why the mix shifts with age
When retirement is decades away, you can hold mostly stocks: you have time to ride out downturns, and growth matters more than stability. As retirement approaches and then arrives, a market crash becomes more dangerous, because you have less time to recover and may be withdrawing, so you shift toward bonds and cash to protect what you have built.
Set a target above based on your timeline and comfort, then rebalance back to it periodically as markets pull it out of line.
The old rules of thumb
A classic starting point was to subtract your age from 100 to get your stock percentage, so a 30-year-old holds 70 percent stocks and a 60-year-old holds 40. As lifespans have lengthened, many now use 110 or 120 instead, keeping more in stocks for longer. These are just starting points, useful for orientation, not gospel.
Why your situation matters more
Age is a useful proxy, but the better guide is your actual timeline and temperament. Someone with a pension and a long horizon can hold more stocks than their age suggests; someone who panic-sells in every downturn should hold less, because the best allocation is the one you can stick with through a crash. Match the mix to when you will need the money and to how much volatility you can tolerate without abandoning ship.
Set your target mix and rebalance to it once or twice a year. Constantly adjusting based on headlines is how good allocations get wrecked.
Frequently asked questions
How should I allocate stocks and bonds by age?
Hold more stocks when young and shift toward bonds as retirement nears, because you have less time to recover from a downturn later. Your exact mix should reflect your timeline and comfort with volatility.
What is the rule of 110 for asset allocation?
Subtract your age from 110 to estimate your stock percentage, so a 40-year-old holds about 70 percent stocks. It is an updated version of the old 'subtract from 100' rule, reflecting longer lifespans.
Why does asset allocation matter more than picking stocks?
Your split between stocks and bonds explains most of your long-run return and risk, far more than which specific funds you choose. Getting the mix right is the key decision.
How often should I rebalance my portfolio?
Once or twice a year is plenty for most investors. Rebalancing brings your mix back to target after markets move it, without the harm of constant tinkering based on headlines.
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