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Young professional invests monthly

📖 The story

Emma, 28, starts right after graduation to put $180 each month into a broadly diversified equity fund. Over the long run she expects 7 % return per year and wants to keep it up for 30 years.

ℹ  Ordinary (end-of-period) payment, 12 installments per year.

Change any number and press "Calculate" – or use "Type in" on the right to watch it entered step by step.

What you learn

See how time turns small amounts into a fortune: over 30 years Emma pays in only about $65,000 – the large rest of the final wealth is compound interest. Those who start early let the money work for them.

In short: Even a modest rate of $180 grows over three decades into a six-figure fortune – time is the greatest lever.
Formula
FV = K0·q^n + R·(q^n − 1)/(q − 1), q = (1+i_eff)^(1/m)
With the example numbers
q = (1+0.0700)1/12 = 1.005654,  n = 30·12 = 360
FV = 180.00 $·(qn−1)/(q−1) = 210,501.47 $
How to read the formula

Every installment earns interest until the end – early installments longer, late ones shorter. The bracket (qⁿ−1)/(q−1) sums up all these differently compounded contributions at once. q is the growth factor per period: from the effective rate p.a. the matching monthly factor is derived via the ¹ᐟᵐ root. Takeaway: it is not the sum of the deposits that counts, but how long each dollar is allowed to work.

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