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Compound interest
%
—

Future value

$108,224
Contributed$49,000
Interest earned$59,224

That's about $4,329 a year, for life — what a 4% withdrawal would pay you without touching the balance.

Show the work
  1. 7% a year, compounded monthly, works out to an effective 0.5833% a month
  2. Months: 20 × 12 = 240
  3. Growth factor: (1 + 0.5833%)240 = 4.0387×
  4. Starting $1,000 grows to $1,000 × 4.0387 = $4,039
  5. $200/month, compounded, grows to $104,185
  6. Future value: $4,039 + $104,185 = $108,224

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