I would add that to a vendor table. then if you want to see it on the form
instead of only queries and reports, add an unbound combo box for vendor
selection and set it to see the table and show that field.

if you don't know how to do this after dropping an unbound box, click on
format, change to and select combo box

double click on the box to go into the properties, set the control source to
vendor

select the row source and select the vendor table then click on the ... to
the right of this in the properties. if your Access is fully loaded, it will
go to a SQL Statement (query design view if you will). if it don't ask to
build based on the table, you will have to select the tables and establish
relationships.

then drop (vendor) and (tax status) from the vendor list into the query and
save/close.

copy that box and paste another one next to the vendor selection box. go
into the properties, row source ... and re-arrange (vendor) and (tax status)
to (tax status)and (vendor) and save/close

save your form and click view and test.

I would also set the tax status field so no one can select from it.