Home Expense Report

Hello, I'm creating an excel sheet to record my home expenses. I would like to create a drop box that shows the categories: Home, Auto, Food, Bills.

Once one of these groups is chosen in the drop box, I would like another drop box to show different categories.

Example 1: From the first drop box, I pick "Home"
A second drop box is now activated showing different categories for "Home": Mortgage Payment, Gas Bill, Electric Bill, etc....

Example 2: From the first drop box, I pick "Auto"
A second drop box is now activated showing different categories for "Auto": Car Payment, Gas, Car Maintenance, etc....

Any thoughts on how I can do this?

Thank you,
Mike

Another source:

http://excelsemipro.com/2011/05/a-dy...list-in-excel/

Thank you all for your help!