I've written a program (attached) that asks for principal, downpayment, interest and term and creates an amortization sheet and a loan payment sheet. When using the loan payment sheet, sometimes people miss a monthly payment. When they do, it computes interest and reverse amortizes the principal. So it may show 0 for payment, 600 for interest and -600 for principal. The problem is that this way our company has to show the 600 as income even though we didn't receive anything. On the Oakwood Loan Payments worksheet, the November payment shows interest that is more than the payment. It should show 600 for interest, 0 for principal, with the extra interest being carried over. I can make it work in VBA with a button, or I can make this work for one month using Excel formulas, but if they miss two payments I'm clueless how to do the carryover. Thanks for your help.