Returns

Compound Interest: Definition

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Simple Definition

Earning money on your earnings. Your gains make more gains over time.

Why It Matters

Einstein allegedly called compound interest the eighth wonder of the world. Here's why: $10,000 invested at 10% becomes $67,000 in 20 years - but $174,000 in 30 years. That extra decade doesn't add $67,000; it adds $107,000. Time is your superpower. Starting at 25 instead of 35 can mean retiring with twice as much money.

Key Points

  • The Rule of 72: divide 72 by your return rate to estimate how long it takes to double (7% return = ~10 years to double)
  • Reinvesting dividends turbocharges compounding - $10,000 in the S&P 500 in 1980 would be $1.1M today with dividends reinvested
  • Starting early matters more than investing more money later - time beats timing

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Common Questions

Earning money on your earnings. Your gains make more gains over time. Einstein allegedly called compound interest the eighth wonder of the world. Here's why: $10,000 invested at 10% becomes $67,000 in 20 years - but $174,000 in 30 years.

Einstein allegedly called compound interest the eighth wonder of the world. Here's why: $10,000 invested at 10% becomes $67,000 in 20 years - but $174,000 in 30 years. That extra decade doesn't add $67,000; it adds $107,000. Time is your superpower. Starting at 25 instead of 35 can mean retiring with twice as much money.

The Rule of 72: divide 72 by your return rate to estimate how long it takes to double (7% return = ~10 years to double)

Reinvesting dividends turbocharges compounding - $10,000 in the S&P 500 in 1980 would be $1.1M today with dividends reinvested

Starting early matters more than investing more money later - time beats timing