June 5, 2026
The Rule of 72

The financial world is full of complex algorithms, dense spreadsheets, and jargon designed to make investing look like a highly complicated...

The financial world is full of complex algorithms, dense spreadsheets, and jargon designed to make investing look like a highly complicated science. You could find yourself thinking that you need an advanced degree just to understand what your money is doing.

But occasionally, a piece of math comes along that is so simple, and so profound, that it completely changes how you view your wealth.

Enter the Rule of 72.

The Rule of 72 is a mental shortcut that helps us quickly (but roughly) calculate how long it will take for our money to double. You simply take the number 72 and divide it by your expected annual return.

If your portfolio is project to grow at a steady 8% a year, you divide 72 by 8. The answer is 9. This means that without you adding another penny, your money is likely to double every 9 years.

It is a neat party trick, but the real value of the Rule of 72 is not the mathematics. It is the emotional relief it provides.

When we don't understand how compounding works, we tend to panic. We feel like we constantly need to be saving more, hustling harder, or chasing high-risk, high-reward investments just to reach our goals. We view wealth creation purely through the lens of our own effort.

The Rule of 72 proves that you do not have to do all the heavy lifting. Time is actually your most powerful asset.

When you realise that a steady, boring, well-diversified portfolio will naturally double your money over a decade, it removes the pressure to take reckless risks. It gives you permission to be patient. You don't need to outsmart the market; you just need to stay in it.

This is the heart of lifestyle financial planning. Your money is supposed to work for you, not the other way around.

When you trust the quiet, relentless math of compounding, you stop checking your portfolio every day. You stop stressing over short-term market dips. You realise that your capital is on a dependable, predictable trajectory.

And when you no longer have to spend your cognitive energy worrying about whether your money is growing fast enough, you can redirect that energy back to where it belongs: your family, your community, and the life you are actually meant to be living.

Make your money work for you.

Liron Mazor

Greengrass Wealth Management is an authorised and licensed independent financial services provider with the Financial Services Board (FSP Number: 19308)
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