#compound-interest

$100/month feels too small to bother with. But run it through 30 years of compounding and the number lands at $122K. Plus the harder lesson: starting at 25 with $100 beats starting at 35 with $200.

Lump sum $50K at 7% turns into $381K in 30 years. Add $500/month and it hits $988K. But inflation cuts that nominal $988K down to $406K of real purchasing power. Both numbers matter.

Compound interest is just earning returns on returns. The math is simple. The reason it's powerful — and the reason most people get it wrong — is that the curve barely moves for the first 10 years.