Originally Posted by Peter Puetz
make the cells a little wider, commatas...
That's not the problem. The "inc" name actually points to the "inc" label, not the value, so the calculation is trying to multiply a string, not a number, and that doesn't work.
Here's how to fix it:
Go to the Insert > Name > Define... menu, click on inc, and click on the Delete button.
Then put the selection on the inc value (10), and name it "inc" by typing into the formula bar, where it says D1. If you know how to used Excel named ranges, this will make a lot of sense, otherwise, you might have to hunt around. It's on the top left, under the "ribbon" of button.