How this calculator works
The solver finds the annual logarithmic growth rate linking the present value, scheduled nonnegative deposits and a target balance. It converts that rate into the selected nominal compounding quote. Dates use actual elapsed days divided by a 365.25-day model year; duration units use that same convention. End contributions occur at completed interval ends; beginning contributions occur at interval starts strictly before the horizon. The real rate uses the exact inflation relationship, and the annual table shows the solved balance path. The opening row includes the first beginning deposit when the horizon is positive; later exact-boundary rows show the closing balance before the next beginning deposit.
Formula
Target = P exp(kt) + sum(C exp(k(t-t_j))). Nominal j = m[exp(k/m)-1], or k for continuous compounding. Real effective rate = exp(k)/(1+inflation)-1.
Worked example
$10,000 growing to $12,100 in two years without deposits implies 10% annual compounding. $100 growing to $144 over two years implies 20%. At 10% nominal growth and 2% inflation, the real effective annual rate is 7.843137%.
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Frequently asked questions
Can the solved rate be negative?
Yes, if the target and cash flows imply a shrinking balance. The target itself must remain positive.
Why might a target have no solution?
For example, a beginning-of-period payment at the final horizon can impose a positive minimum value. Some targets also exceed the supported numeric range.
Does a date term use Actual/365 Fixed?
No. This growth model uses actual elapsed days divided by 365.25 for the model-year length. It is not a contract-specific money-market day-count calculator.