rate - The interest rate per period. We divide the value in C6 by 12 since 4.5% represents annual interest: nper - the total number of payment periods for the loan, 60, from cell C8. pv - The present value, or total value of all payments now, 5000, from cell C5. start_period - the first period of interest, 1 in this case, since we are calculating principal across the entire loan term. end_period - the last period of interest, 60 in this case for the full loan term. With these inputs, the CUMPRINC function returns 5,000, which matches the original loan value as expected.

### Dave Bruns

Hi - I’m Dave Bruns, and I run Exceljet with my wife, Lisa. Our goal is to help you work faster in Excel. We create short videos, and clear examples of formulas, functions, pivot tables, conditional formatting, and charts.