IPMT Function

The IPMT function calculates the interest portion of a payment for a specified period in the life of a loan, given the amount of the loan and a given rate of interest. It is based on the same equation as the FV Function.

IPMT(period = value, pv = value, i = value, nper = value, fv = value, paybegin, byref(context))

Note: Paybegin is either 1 or 0, indicating that the payment is made at the beginning or end of the period.

Arguments	Data Type	Description
period	Float	Specific period ( 1 - nper )
pv	Float	Present value
i	Float	Interest per period
nper	Integer	Number of periods
fv	Float	Future value
paybegin	Integer	1 = beginning of period 0 = end of period Default: 0
context	PMT_CONTEXT	Payment context (see following note)

Note: The context, which is used internally to improve the efficiency of repetitive IPMT calls, must be declared as PMT_CONTEXT and passed using byref().

/*  In the following example period and interest are
**  EntryFields of DataType Float. A specific period
**  would be entered in the period field. There is
**  also a ButtonField named btn_ipmt. The frame
**  script is shown below. The loan is for $10,000
**  for 48 months at 7% interest per year.
*/
on initialize =
declare
    context = PMT_CONTEXT;
enddeclare
on click btn_ipmt =
begin
interest = ipmt(period = period,
       pv = 10000,
        i = .07/12,
     nper = 48,
       fv = 0,
paybegin = 0,
  context = byref(context));