### ann()

#### Syntax

**ann**(rate,nper,pmt,pv,fv[,prd])

#### Description

Evaluates an unknown for an annuity and returns the result.

The first five arguments are mandatory, but you can replace any one of them with '?' which is the unknown value returned by the function.

Parameters: *rate* is the interest rate per payment period; *nper* is the number of payment periods, which should be an integer greater than zero; *pmt* is the payment made to you (or by you) at the end of each period; *pv* is the amount paid to you (or by you) at the start of the first period; *fv* is the amount paid to you (or by you) at the end of the final period; *prd* is optional and represents a specific period which must be between 1 and *nper*; it is used for obtaining the split of interest and capital payments in a period.

The convention is that positive values for *pmt, pv* and *fv* denote a payment made *to you*, and negative amounts denote a payment made *by you*. It is important to ensure that *rate, nper* and *pmt* all refer to the same period length. The annuity is evaluated so that the sum of all payments made to you (or by you) when compounded at the interest rate evaluates to zero.

The following example shows that, a 25 year mortgage for $30000 at 11% pa interest payable monthly in arrears has monthly payments, paid by you, is equal to:

#### Example

###### Calculate lAmount as *rnd*(**ann**(.11/12,25*12,'?',30000,0),2)

###### ; returns -294.03