**Description** Computes the net present value of an investment with flexible periods.

**Syntax** XNPV (*rate, values, dates*)

Argument | Description |
---|---|

rate |
The annual interest rate. |

values |
A range reference or array constant containing a series of payments to the investment. The first value in the range or array constant is the cost at the beginning of the investment; it is usually negative or 0. Positive values represent payments to the investment. Empty cells are evaluated as 0. |

dates |
A range reference or array constant containing the dates each of the payments in values was made. The first date in the range or array constant is the initial investment date. All the other dates must be later than the initial date, but need not be in chronological order. All dates are truncated to integers.There must be the same number of potential values in dates as in values. |

**Remarks** XNPV calculates net present value similarly to NPV, only XNPV allows you to enter the exact dates of the payments. This may be useful in cases where, for example, the institution offering the investment is writing a contract that sets down the exact payment schedule.

All computations are based on a 365-day year.

**Equation**

...where d_{i} is the *i*th, or last, payment date, d_{0} is the 0th payment date, and P_{i} is the *i*th, or last, payment.

**Examples** This function returns -937.41:

- XNPV(0.6,{-1000,600,600},{"1/1/85","1/1/90","1/1/95"})