This function calculates the cumulative interest paid on a loan during a specified period.
This function assumes equal payment amounts over the period of the loan.
The period passed in any argument in the function must be is consistent. The function takes up to six arguments: the first argument (i) requires the interest rate for the calculation period; the second (p), fourth(s), and fifth(e) arguments specify the periods used in the calculation. These periods must match, so to calculate the annual cumulative interest paid, use the annual interest rate, and the number of periods in years. Bear this in mind when using hard-coded values in the function.
This function is equivalent to the Excel function CUMIPMT.
The function must be used in a line item with the Format: Number.
CUMIPMT(i, p, v, s, e, [mode])
|i||interest rate per period||Number (percentage)||Numeric hard-coded value, line item, or property|
|p||the number of periods over which the loan is repaid||Number||Numeric hard-coded value, line item, or property|
|v||the current loan balance||Number||Numeric hard-coded value, line item, or property|
|s||the first payment period used in the calculation. Cumulative interest is calculated between this point and the end period.||Number||Numeric hard-coded value, line item, or property|
|e||the calculation end period. Cumulative interest is calculated between the start period and this point.||Number||Numeric hard-coded value, line item, or property|
|mode (optional)||when the payments are made. If the value is not provided, or the value is zero, the function assumes payments are made at the end of each period; a non-zero value means payments are made at the start of each period.||Number||
Numeric hard-coded value, line item, or property
The formula to calculate the cumulative interest paid in the second year is:
CUMIPMT(Interest Rate, Period of loan, Loan amount, Period Start, Period End, 0)
where the line items use this data:
|Period of loan||12|
Use the same figure for the start period and end period to find the interest for a single year.
Using the same data, the formula to calculate the cumulative interest paid in the first month only is:
CUMIPMT(Interest Rate/12, Period of loan*12, Loan amount, Period Start, Period End, 0)
Because the data is in years, the period interest rate and the number of payments over the period of the loan must be recalculated. To do this:
- divide the Interest Rate by 12, and
- multiply the Period of loan by 12.