Asset Allocation by Age — Matching Risk to Time Horizon

Asset allocation is the split of a portfolio among broad categories — commonly stocks, bonds, and cash. The reason age enters the conversation is time horizon: how many years remain before the money is needed shapes how much short-term swing a portfolio can absorb without forcing a sale at a bad moment.

Why horizon drives the mix

Stocks carry more short-term volatility and, historically, more long-term growth; bonds and cash carry less of both. A long horizon can ride out a downturn because there is time for a recovery before withdrawals begin. A short horizon cannot, because a decline right before the money is spent leaves no time to recover. This is why conventional guidance shifts weight from stocks toward bonds as the spending date approaches.

The rules of thumb, and their limits

Old shorthand suggested holding a bond percentage equal to your age, later loosened to figures like 110 or 120 minus your age in stocks. These are conversation starters, not answers. They ignore the size of the goal, other income sources, risk tolerance, and whether the money has one deadline or many. A rule that fits a single retirement date fits a multi-decade goal poorly. Treat the formulas as a starting sketch, not a prescription.

What age leaves out

Age is a proxy for horizon, and horizon is only one input. Two people the same age with different goals, savings, and tolerance for seeing a balance fall may reasonably hold very different mixes. Allocation also interacts with rebalancing, because a target mix is only meaningful if it is maintained. The right allocation for a specific person depends on circumstances that belong with a qualified professional, not a general table.

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Educational only. Not financial advice. Results not guaranteed. We are not financial advisors.