The magic of compound interest is one of the great financial forces of the universe—right up there with gravity, but significantly more useful for retirement planning. Yet, for many, it remains an abstract concept, floating somewhere between confusing maths and financial wizardry. Enter the Rule of 72, a brilliantly simple trick that makes sense of this wealth-building sorcery. Wealth grows like a golden tree—thanks to compound interest! What's the Big Idea? (And Why Should I Care?) The Rule of 72 is an elegant little formula that estimates how long it takes for an investment to double at a given annual return. You simply divide 72 by the interest rate. So, if your money is growing at 6% per year, it will double in about 72/6 = 12 years. Want to double your money in 8 years? You’ll need a