What else could we do if we turned iterations off? So back where we started with Excel, warning me, there is a circular reference here.

What we could do is calculate the interest without linking it into the model. So let's do that. I'm just going to remove what's on line 17.

So I've got the interest calculated for me nicely here. It just isn't linked back into the cashflow and therefore the circular reference has gone. The blue arrows are gone. The warning down here in the gray cells is also gone. The difference between the interest and the amount that should be in the cashflow is clearly the whole lot.

That's the amount of error that's in the model. I'm going to change these numbers so that they are negatives. So I'm going to say minus D27 times C31, and then copy that across.

I'm going to take these numbers and I'm going to copy them as values into the interest line.

That's home, paste, And then I want paste values.

And you can see what's happened. We've added 100 of interest into the first year. Excel has recalculated, therefore you need to draw down 1,100 and interest on 1,100 is not 100, it's 110. So I'm out by 10 in the first year, 30 in the second, 30 and 50. But all I need to do is I just keep copying and pasting it as values, home paste values. And it's now saying, okay, so if you need to now borrow 1,110, interest on that is 111. The difference between what you've got in one line and the other is now down to one in the first year, 4, 4, and 7. And we just keep on going edit.

We just keep on going paced values that's still highlighted. So I can just go back in here again and go home paste values and I can keep doing this. And you'll notice that gap at the bottom is getting smaller and smaller and smaller each time I do this, it's never going to be quite zero, but if you do this enough times, you can get the difference down to a very, very low level.

Having done that about 10 times now, my error is less than 0.0000.

So it's somewhere in the fifth decimal place. It's never going to be exactly zero. And that's kind of where we got to by turning on iterations only. Now we don't have the problem that if we make a circular reference by mistake, that Excel will just calculate it quite normally.