Discussion on:

Office challenge: How would you improve this Excel sheet?

I'm not sure what kind of features you want in the finished workbook but for a starter I'd format cell B6 as percentage and add this code to the sheet to clear the cells when they have selected a different option. http://www.allaboutoffice.co.uk/images/changecode.png

I willmake the following changes before releasing for distribution.
1. Formatting to show what type of value user has to enter. For example I will add % to the heading at B5 , (#) to C5, ($) to rest of the columns, so that the user will understand a percentage has to be entered.
2. Enter comment s about the type of input expected in cells B6:G6 so that this will help the user to enter correct inputs.
3. Protect the sheet and allow only A6:G6 cells for input. This is to make sure the user does not change the formulas.