Portfolio Allocation by Age Calculator

This calculator suggests a growth versus defensive split for your investments based on your age and risk appetite, and shows the dollar split for your portfolio, a useful starting point for thinking about how your money should be invested in New Zealand. The idea behind age-based allocation is simple: the further you are from needing the money, the more you can hold in growth assets like shares, because you have time to ride out the inevitable ups and downs, while as you approach the point of drawing on it you shift toward steadier defensive assets to protect what you have built. A widely used rule of thumb sets your growth percentage at about one hundred and ten minus your age, with the remainder in defensive assets, and you can nudge it up or down depending on whether you are conservative or comfortable with risk. You enter your age, your portfolio value, and your risk appetite, and the calculator returns the suggested growth and defensive percentages and the dollar amount for each. Use it to sense-check whether your KiwiSaver fund or investment mix roughly fits your stage of life, and as a prompt to review your fund choice. This is a rule of thumb and a starting point, not personalised advice; your goals and timeframe matter as much as your age, so seek advice for big decisions.

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70% growth · 30% defensive
suggested allocation for your age and risk appetite
Growth assets$70,000
Defensive assets$30,000

Based on the 110-minus-age rule of thumb, adjusted for risk appetite. A starting point, not advice; your goals and timeframe matter too. Seek advice for big decisions.

How it works

The suggested growth percentage is 110 minus your age, adjusted up or down for your risk appetite, and capped between 0 and 100. The defensive percentage is the remainder. The calculator applies those percentages to your portfolio value to show the dollar amount for growth and defensive assets.

Worked example

At age 40 with a balanced risk appetite, the rule suggests 110 minus 40, which is 70 percent growth and 30 percent defensive. On a 100,000 dollar portfolio that is 70,000 dollars in growth assets and 30,000 dollars in defensive assets.

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