Future Value Separates Contributions from Modeled Growth
The future-value calculation compounds the starting principal and incorporates recurring contributions according to the timing assumptions in the calculator. A contribution made earlier has more periods in which to participate in modeled growth than the same contribution made later.
The entered return is an assumption, not a forecast. Fees, taxes, volatility and irregular cash flows can make a real investment path differ substantially even when the ending average return is similar.
Future value combines three things that are easy to mix together: the money you start with, the money you add later and the growth earned along the way. Contributions made earlier have more time to compound than contributions made near the end, so contribution frequency can matter. Because the return is assumed rather than known, the projection is most informative when you test a range of rates and compare how much of the ending value came from your own contributions versus modeled growth.
Frequently Asked Questions
Why does contribution timing matter?
Money added earlier is present for more compounding periods under the model.
Does the result predict an investment balance?
No. It is a deterministic projection using the return and contribution assumptions you enter.
Why does contribution timing affect future value?
Money contributed earlier has more periods in which it can earn the assumed return. Later contributions have less time to compound before the end of the projection.
Methodology & Related Tools
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