We're going to do four different types of debt repayments. In each case, the loan amount is going to be 100,000, at 10% interest rate and a loan life of five years. In the first one, we're going to work out a fixed payment each period, including both interest and principal with a balance reducing to zero by the end of the fifth payment. To do that on the repayment line that's marked up in blue, we're going to use Excel's PMT function. That's the function that gives us a constant payment amount each period that comprises both interest and principle. Notice that in our corkscrew or base calculation, we have the opening balance, the drawdown add the interest at 10% each time gives us another subtotal, and that is what we're going to try to pay off in the repayment line. We'll enter the formula equals PMT and like all Excel functions, it will start to prompt us for what is needed next. The first item that's requested is the interest rate. We know that it's 10%. Let's fix that. It then asks for nper. That stands for the number of periods, how many payments are likely to be made. Five of them. Put the dollar signs on that too. PV present value, that's the amount of the loan that you are trying to repay. That's 100,000. Also fix that, and then you'll see two further items in square bracket. FV is future value. You can just leave that out or leave it blank. And the other square bracket input is type, so I don't need to put anything in there. Press enter. That gives me a 26,000 repayment amount. So after five payments like this, it should reduce the loan down to zero. Let's check if I copy that across to the right and you can see yes, after five payments including interest, it reduces the balance down to zero. Now the problem we've got here is that we haven't told Excel to stop the payments once the loan hits zero, and so there's a sixth payment here. What we need to do is ask excel to only put the payments in to the extent that there's any debt left over still to repay. If there's no debt, we should have no payments. So in the sixth year, that number ought to be zero. The way we do that is we put in a min function minimum of the PMT as we had previously worked it out, and the value of the debt, the amount That is owed just before we make the payments. Now we need to be careful here because the PMT is giving us a negative number, so what we'll do is we'll make both of them positive. Change the sign on the PMT. So now both the PMT function and what's on line 17 there both positive numbers. We're asking Excel, give me the minimum of those two positive numbers when you've worked out which one that is. Then call the whole thing a negative. Let's copy that across and you'll see it stops paying in the sixth year because it's saying it's the minimum of my usual payment, 26,379, or the balance of the debt, which is zero.