All versions
Financial
The Excel MIRR function returns a modified internal rate of return that uses separate financing and reinvestment rates — fixing IRR's unrealistic reinvestment assumption.
Quick answer:
=MIRR({-10000,3000,4200,5000}, 8%, 6%) // about 9-10%
Syntax
=MIRR(values, finance_rate, reinvest_rate)
| Argument | Description | |
|---|---|---|
values | Required | Cash flows in time order (with at least one negative and one positive). |
finance_rate | Required | The rate paid on money invested (cost of borrowing). |
reinvest_rate | Required | The rate earned reinvesting positive cash flows. |
How to use it
MIRR returns a modified internal rate of return that uses separate financing and reinvestment rates — fixing IRR's unrealistic reinvestment assumption.
=MIRR({-10000,3000,4200,5000}, 8%, 6%) // realistic return
Try it: interactive demo
Live demo
This is the formula pattern MIRR uses — copy it into Excel with your own numbers.
Result: computed in Excel
Practice workbook
Download the free MIRR practice workbook
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Frequently asked questions
Why use MIRR over IRR?
IRR assumes every positive cash flow is reinvested at the IRR itself, which is often unrealistic. MIRR lets you set a real reinvestment rate.
What are the two rates?
finance_rate is what you pay on negative flows; reinvest_rate is what positive flows earn when reinvested.
Which Excel versions support it?
All modern versions.
Why might it return #NUM! or #VALUE!?
Out-of-range arguments (e.g. negative rate or settlement after maturity) give #NUM!; non-numeric inputs give #VALUE!.
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