Calculates the internal rate of return for a list of payments that take place on irregularly spaced dates.

**Sample Usage**

XIRR(A3:A7, B3:B7)

**Syntax**

XIRR(values, dates, [guess])

- values - The series of payments entered as a cell reference.
- dates - The date values associated with the series of payments.
- guess - [OPTIONAL] Estimated internal rate of return value. The default is 10%.

**Examples**

XIRR(A3:A7, B3:B7) returns the internal rate of return for payments A3:A7 that take place on dates B3:B7. with an internal rate of return value of 10%.

**Notes**

- If the days specified in dates are at a regular interval, use IRR instead.
- Each cell in values should be positive if it represents income from the perspective of the owner of the investment or negative if it represents payments.
- values must contain at least one negative and one positive cash flow to calculate rate of return.
- XIRR is closely related to XNPV. The rate of return calculated by XIRR is the interest rate corresponding to XNPV = 0.