Asset allocation by age: How much should move from equity to debt over time
A simple rule of thumb for splitting your money between equity and debt, and why the split shifts as you get older.
Most people know it is unwise to keep all their money in one place. Fewer know how to decide how much belongs in equity, how much in debt, and whether that split should ever change. One simple rule of thumb ties the answer to your age.
This article is for educational purposes only and should not be treated as investment advice. Investors should consult an independent financial advisor before making investment decisions.
What is asset allocation, and what is the 100 minus age rule?
Asset allocation is the way you divide your investments across asset classes, mainly equity and debt. Age serves as a rough stand-in for your investment horizon: the longer you have before you need the money, the more time your portfolio has to recover from a downturn. One widely used rule of thumb ties the two together directly.
Equity allocation (%) = 100 − your age
Debt allocation (%) = your age
The logic is that a younger investor may have a longer time horizon to recover from a market downturn. As the investment horizon shortens, the formula gradually shifts the portfolio toward debt.
What do the numbers look like at different ages?
The table below applies the formula at three ages, purely to illustrate how the maths works. These are not recommended allocations for anyone of that age, since the right mix for an actual investor depends on more than age alone, covered further down.
| Age |
Equity allocation |
Debt allocation |
| 30 |
70% |
30% |
| 36 |
64% |
36% |
| 60 |
40% |
60% |
At age 30, the formula shows 70% equity and 30% debt. At 36, it works out to 64% equity and 36% debt. By 60, it has shifted to 40% equity and 60% debt. Treat these as a demonstration of the formula, not a target to copy.
What is the difference between equity and debt?
The two asset classes do different jobs in a portfolio.
| Aspect |
Equity |
Debt |
| What it includes |
Shares and equity mutual funds |
Bonds, fixed deposits and debt funds |
| Growth potential |
Higher over long periods, though not guaranteed |
Generally lower |
| Volatility |
Higher, with sharper ups and downs |
Generally lower |
| Role in a portfolio |
Long-term growth |
Stability and steadier returns |
Debt is generally steadier, but it is not risk-free. Interest rate changes and credit quality can still affect returns. If you're new to the equity side and want to understand the basics before you start, our step-by-step guide to buying your first stock is a good place to begin.
Is this rule enough on its own?
No. The rule uses age as a stand-in for things that actually matter more than age itself. Worth weighing before you settle on a split:
- Investment horizon for the specific goal, which may differ from what your age alone suggests.
- Financial goals, since money needed in three years belongs to a different bucket than money untouched for twenty.
- Income stability, since the ability to meet regular expenses without relying on investments can affect how much investment risk you can reasonably take.
- Existing investments, including provident fund savings that already tilt your overall exposure.
- Liquidity requirements, or how much you may need on short notice.
- Risk tolerance and risk capacity, which differ. Tolerance is the volatility you are comfortable with emotionally; capacity is what your finances can actually absorb.
Some investors also allocate by goal instead of by age, keeping money for a near-term expense in debt regardless of how old they are. Equity and debt mutual funds both operate under the SEBI (Mutual Funds) Regulations, 1996 , which set disclosure standards for fund houses.
Should you rebalance as you age?
Rebalancing isn't only about getting older. Many investors do review and adjust their mix periodically as their age or life stage changes, but a more immediate trigger is the market itself. A strong run in equities can push your equity share well above your intended split without you doing anything, and a sharp fall can do the opposite. Rebalancing means bringing the mix back toward what you originally intended, regardless of what caused it to drift.
How often you do this depends on your goals and circumstances, not a fixed age-based schedule. Rebalancing can involve costs and taxes, so it is worth checking both before you sell anything.
How can Chola Securities' Asset Allocation Calculator help?
The Chola Securities Asset Allocation Calculator is a free tool that takes just one input: your age. It shows the resulting equity and debt split as a donut chart, and you can adjust your age with a slider to see how the mix changes.
Its output is illustrative and is not investment, tax or legal advice. Use it to start the conversation with yourself, then adjust for your own situation, including the factors listed above.
Final thoughts
The 100 minus age rule is a simple way to think about a question most investors put off. It works best as a reference point, alongside the goals, horizon and risk factors that actually decide your split.
If you are ready to put a plan into practice, you can begin through the Chola Securities KYC portal.
Disclaimer: Cholamandalam Securities Limited (CSEC) is a SEBI-registered stock broker and depository participant. CSEC does not provide investment advisory services. Investors are advised to consult an independent financial advisor before taking any investment decisions.