# Thread: Interest Calculator with a twist

1. ## Interest Calculator with a twist

I am trying to create my own excel calculator that will solve for cell G4. What is the unpaid balance at the date of the sale with the variables taken into consideration from cells D3 through D13. So, if a \$500,000.00 loan was amotorized over 40 years, had an initial rate of 6% and the first payment date was 12/1/2000…..the result would be simple. However, with a twist thrown in there where the rate was reduced from 6% to 4% from 5/15/2002 through 5/15/2003, that would change things. Then….payments stopped for whatever reason on 8/1/2009 and the property was later sold on 10/15/2011.

2. Hi there,

I'm not sure I've got it exact, so check the numbers carefully and post back if you need any modifications but try this as a start.

3. Ken,
Thank you so much, sir. That is very close. The only modification that I can see is taking the hypothetical stopped payment into consideration. I.e., last payment date. So, for example..... if the payments stopped on 12/1/2010.....the interest would compound and the balance would increase.

4. Try this out. I inserted a new column and re-did your formulas a bit, but let me know if this looks reasonable...

It should now deal with the last payment date issue, as well as accrued interest (daily) until payout.