Day 55 · Sunday, 27 September 2026
From the archive
Report how much loan interest was deductible in each of two tax years
CUMIPMT sums just the interest portion of a loan's payments between two period numbers you name, instead of amortizing the whole schedule to get there — and the figure it returns shrinks every year, because a level payment sends more toward principal as the balance owed goes down.
Task:
You handle equipment accounting for a construction company that financed a $60,000 excavator over 5 years, in 60 equal monthly payments, at a 6% annual interest rate. The accountant preparing the tax filing needs the interest expense for each of the first two years reported separately, since only the interest portion of a payment is deductible. In B5, use CUMIPMT to find the total interest paid across Year 1 (payments 1 through 12). In B6, find the total interest paid across Year 2 (payments 13 through 24).
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