The Power of Compound Interest
Albert Einstein reportedly called compound interest the eighth wonder of the world: 'He who understands it, earns it; he who doesn't, pays it.' Unlike simple interest, which is calculated only on your initial deposit, compound interest calculates interest on your principal PLUS all previous interest earned.
Over time, this compounding creates an exponential growth curve, turning modest monthly savings into substantial wealth portfolios.
The Compound Interest Formula
The formula to estimate future value with compound interest is:
- A = P(1 + r/n)^(nt)
- A = Final balance, P = Initial principal amount, r = Annual interest rate (decimal)
- n = Number of times interest compounds per year, t = Total years invested
Note: Rule of 72: A quick shortcut to estimate how long it takes your money to double is to divide 72 by your annual interest rate. For example, at an 8% return rate, your money will double in 9 years.
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