What is the Rule of 72?

Years to double ≈ 72 ÷ Annual Return. 8% → ~9 years. 12% → ~6 years.

What annual return is realistic?

Stock market long-term average: 8-12%. Index fund investing: 8-10%. Above 15% is excellent.

Simulate long-term compound growth — the 8th wonder of the world.

Initial Investment

Annual Return (%)

Investment Period (years)

Annual Addition

Final Amount

Total Profit

Return Rate

💡 Rule of 72

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