Author name: Steve K.

Steve is a 40-something mechanical engineer living in South Korea. He started investing in 2009, lost money picking individual stocks, and since 2024 has rebuilt his retirement accounts around S&P 500 and Dow Jones index funds. He writes here about the slow, unglamorous work of building passive income alongside a full-time job, and works with an AI assistant to research, draft, and fact-check. Nothing on this site is investment advice.

Cross-section of a cut tree stump showing dozens of concentric annual growth rings, the outer rings enclosing far more area than the inner ones
Investing for Beginners

How Long Until Your Money Doubles?

A coworker asked how long his money takes to double and I could not answer without a spreadsheet. The Rule of 72 does it in three seconds, it is accurate to within a month between 6 and 9 percent, and it exposes the uncomfortable part: 54 percent of a 40-year outcome arrives in the final decade.

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