When editing a model we may often find that we want to remove items. Maybe they had use in the past. But now we find they're a bit redundant. However, if we just start deleting out rows, we may find some problems occur. For instance deleting rows may mean that dependent cells now return #REF. Imagine you want to delete row one from your model, but unfortunately, you also know that an A7 there's a formula and it says equals A1. We need Row one in A7. It's now gonna say equals. Oh, there's nothing there and it's gonna say equals hash ref. So we can't just randomly delete rows because we may find that they're linking to other cells and those cells will then say Oh, there's nothing for us to link to Instead what we need to do is Trace dependent cells. So if I'm in A1, I turn on my Trace dependence, so alt m d and then I would edit that formula that I found in A7. Maybe I would change it somewhere else, maybe I'd delete it, and I then only delete when trace dependence finds no Links at all. So we're going to A1 turn on trace dependent. What do I find this dialog box? The trace dependence command found no formulas that refer to the active cell. You're now safe to delete that cell. You may also want to trace precedence to find cells that may now be redundant. Maybe A1 was coming from A2. So if you now delete A1, you may find that the selling A2 is now completely redundant in how doesn't link to anywhere. It's just a figure in a Cell. It's worth tracing precedence to find if you've got any redundant cells that can be gotten rid of.