IPMT(R, P, NP, PV, FV, [T])

Description
This function returns the interest payment for a specified period for an loan or investment based on periodic, constant payments and a constant interest rate. Make sure that the units used for R and P are consistent. For example, for a 5-year loan with 12% annual interest, if you make payments monthly, use 12%/12 for (monthly) R and for NP.

Parameters
R
Interest rate per period

P
The period for which the interest will be calculated (an integer)

NP
The total number of payment periods

PV
The present value of the investment

FV
The future value or a cash balance you would like to attain at the end of the last period

T
(Optional) timing of the payment:
0 payment is made at the end of the period
1 payment is made at the beginning of the period

Example
IPMT(10%/12, 1, 24, 2000, 0, 0) = 16.6667