This article describes the formula syntax and usage of the CUMPRINC function in Microsoft Excel.
Description
Returns the cumulative principal paid on a loan between start_period and end_period.
Syntax
CUMPRINC(rate, nper, pv, start_period, end_period, type)
The CUMPRINC function syntax has the following arguments:

Rate Required. The interest rate.

Nper Required. The total number of payment periods.

Pv Required. The present value.

Start_period Required. The first period in the calculation. Payment periods are numbered beginning with 1.

End_period Required. The last period in the calculation.

Type Required. The timing of the payment.
Type 
Timing 
0 (zero) 
Payment at the end of the period 
1 
Payment at the beginning of the period 
Remarks

Make sure that you are consistent about the units you use for specifying rate and nper. If you make monthly payments on a fouryear loan at an annual interest rate of 12 percent, use 12%/12 for rate and 4*12 for nper. If you make annual payments on the same loan, use 12% for rate and 4 for nper.

If rate ≤ 0, nper ≤ 0, or pv ≤ 0, CUMPRINC returns the #NUM! error value.

If start_period < 1, end_period < 1, or start_period > end_period, CUMPRINC returns the #NUM! error value.

If type is any number other than 0 or 1, CUMPRINC returns the #NUM! error value.
Example
Copy the example data in the following table, and paste it in cell A1 of a new Excel worksheet. For formulas to show results, select them, press F2, and then press Enter. If you need to, you can adjust the column widths to see all the data.
Data 
Description 

0.09 
Interest rate per annum 

30 
Term in years 

125000 
Present value 

Formula 
Description 
Result 
=CUMPRINC(A2/12,A3*12,A4,13,24,0) 
The total principal paid in the second year of payments, periods 13 through 24 
934.1071234 
=CUMPRINC(A2/12,A3*12,A4,1,1,0) 
The principal paid in a single payment in the first month (68.27827) 
68.27827118 
Notes:

You divide the interest rate by 12 to get a monthly rate, and you multiply the years the money is paid out by 12 to get the number of payments.

In Excel Web App, to view the result in its proper format, select the cell, and then on the Home tab, in the Number group, click the arrow next to Number Format, and click General.