I have found 3 sets of identical instructions for getting data tables to work
(including the simple instructions included with excel 2003) but my data
table will not work.

I enter the variables that I want in a column (A20:A29 in this case). I
enter a link to the formula that I want in B19 (in this case '=Profit', which
is defined elsewhere). I get the correct answer for B19 (based on the
non-variable value I have above). In this case the profit function depends,
among other things on a variable "ResponseRate" which is a named range
corresponding to cell E4.

So, I have everything set up correctly and I highlight the correct cells,
select Data - Table, Column Reference and then type in either "Response
Rate" or "E4" (I've tried both). The Data table instanly fills in the
columns, BUT ONLY FOR THE CURRENT VALUE OF "ResponseRate".

I know the error is not with my defintion of the formula I have in the range
defined as "profit". If I update my actual "ResponseRate" then my profit
formula gives me the right answer. But my damn data table just gives me 10
copies of the exact same variable.

Please help me with this. I'm going to go insane.