I set up a drop-down list for my spreadsheet with the options "Fax, Mail,
Pick-up, Interoffice". When I pick fax, the next block in that column only
gives me the options, "Mail, Pick-up, Interoffice". If I pick one of those
three, the next block has two options. I want to be able to reuse the options
multiple times.

I selected the range G3-G40, went under the Data menu, picked Validation,
picked List from the Allow drop-down box, and entered "=(J2-J5)" in the
Source text box.

What am I doing wrong?