Loan calculator model Annuitet and Regular Formula addition

Hello

I have built a quite extensive loan calculator, for both Annuitet and even repayments, and the calculator is working fine.
The formulas for it are a bit complex (perhaps I wrote them a bit too complicated )

Anyway, I want to be able to pay into the principal amount at any given time in the model, but I have no idea how to adjust the formulas to replicate that?
Can anyone assist?

I have attached the document for further verification.

MAny Thanks!
Loan Calculator.xlsxLoan Calculator.xlsx

Originally Posted by helgimarg

Hello

I have built a quite extensive loan calculator, for both Annuitet and even repayments, and the calculator is working fine.
The formulas for it are a bit complex (perhaps I wrote them a bit too complicated )

Anyway, I want to be able to pay into the principal amount at any given time in the model, but I have no idea how to adjust the formulas to replicate that?
Can anyone assist?

I have attached the document for further verification.

MAny Thanks!

You are making a simple task a very complex by using those formulas

Excel has the following three function that you could have used instead

To find the monthly interest payment use IPMT
To find the monthly principal paid use PPMT
And you can use CUMPRINC and it's addition with loan amount to find the remaining principal

And between the words, your columns for principal repayment and outstanding principal are all wrong

Is anyone able to assist in any way?

Here you go:


Loan Calculator.xlsx