Compounding 101 for Beginners

What compounding is: the Rule of 72

Compounding means interest earns interest: this year’s 5% joins the principal next year, so the curve steepens with time. Mental shortcut: 72 divided by the annual return equals doubling years — 6% doubles in ~12 years, 8% in ~9.

It cuts both ways: borrowed money (credit cards, personal loans) compounds against you. Lesson one is always clearing high-interest debt before investing.

Why dollar-cost averaging suits beginners

A beginner’s biggest enemy is not picking wrong — it is stopping. Fixed monthly investing automates discipline: downturns buy more units automatically (the smile curve), no timing needed.

Small amounts are fine. $100 a month at 7% for 30 years is about $122,000 — the key number is 30 years, not $100. Stay consistent first, scale up later.

The dividend myth: payouts are not profit

Dividends come out of net asset value: the NAV drops by the payout on ex-dividend day, so you receive your own money from left hand to right. Compare funds by total return, never by yield alone.

A 10% yielder with shrinking NAV loses long-term to a 3% yielder with steady growth. Run “payout” vs “reinvest” in the calculator and see the ending-asset gap yourself.

Model it in three steps

Open the compound calculator: enter lump sum, monthly amount, and years; set the annual return (start with a conservative 5–8%) and yield; then compare ending assets and toggle payout vs reinvest.

Ask three questions after: can I keep this up that long? Is the return assumption too rosy? Am I fine with reinvesting? Three yeses and the plan counts.

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