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Don't miss the last double: the Rule of 72

Returns growing

In the world of investing there's a nifty rule that simplifies the complex concept of compound interest – the Rule of 72. This rule serves as a quick and easy way to estimate how long it will take for an investment to double in value based on its annual rate of return.

The formula is straightforward: divide 72 by the annual interest rate, and voila! You get an approximate number of years it will take for your money to double. For example, if you have an investment with a 6% annual return, it would take roughly 12 years for your initial investment to grow into twice its original value (72 ÷ 6 = 12).

The Rule of 72 isn't a precise calculation, but it provides a close enough estimate for quick financial planning. 

Now let’s get into the second component, time.The beauty lies in the compounding effect – the earlier you start investing, the more times your money has the opportunity to double.

Imagine two individuals, Alice and Bob, both with the same annual rate of return on their investments. However, Alice starts investing in her twenties, while Bob decides to begin in his forties. Despite having the same rate of return, Alice's money will undergo more doubling cycles, thanks to the extra years it has to compound.

Graph showing Alice vs Bob's investment returns. Starting early helps for your money to double more times

It's a matter of simple math. The longer your money compounds, the more significant the impact. If Alice's investment doubles every 10 years, she might experience three or four doubling cycles by the time Bob makes his first investment. While Bob’s money still earns the initial few doubles, because he doesn’t have as much time invested he misses out on the later, bigger doubles; 1 turns into 2, 2 to 4, 4 to 8, 8 to 16. But Bob may not have enough time to get the 16 to 32 doubling!

The key takeaway here is the exponential nature of compounding. Starting early doesn't just give your money more time; it opens the door to multiple compounding cycles that can significantly boost your overall returns. Time becomes your ally in the wealth-building journey.

So, whether you're a recent graduate or someone contemplating their first investment, remember the Rule of 72 and the power of starting early. It's not just about the initial investment; it's about the countless opportunities your money has to grow and multiply. Take advantage of time, and let compounding work its magic on your financial future.

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