⚠️ This post is for educational purposes only and does not constitute financial advice. See our full disclaimer.
Einstein allegedly called compound interest the eighth wonder of the world. Whether or not he actually said it, the math backs up the sentiment.
The Simple Math
If you invest $500/month at a 7% annual return, here’s what happens:
- 10 years: $86,500 (you contributed $60,000)
- 20 years: $260,500 (you contributed $120,000)
- 30 years: $607,000 (you contributed $180,000)
That extra $427,000 in year 30? That’s compound interest doing the heavy lifting.
Three Rules to Maximize It
1. Start Now, Not Later
Every year you delay costs more than you think. Starting 5 years earlier on a $500/month investment adds over $200,000 to your 30-year total.
2. Don’t Interrupt Compounding
Withdrawing early or pausing contributions breaks the chain. Automate your investments so you’re not tempted to skip months.
3. Reinvest Everything
Dividends, interest, capital gains — reinvest all of it. Compounding only works when returns generate their own returns.
The AI Angle
Modern robo-advisors like Betterment and Wealthfront automate reinvestment and tax-loss harvesting, removing human error from the compounding equation. We’ll review these in detail in a future post.
