I created a pivot table that draws on a very large set of data - the file is
7MB. I have since removed most of the data and slimmed the table down to only
10% of what was referenced before. The file is still 4MB. The table or
worksheet still seems to contain some data/links that it no longer needs. I
have removed all the fields and refreshed but this doesn't work.

I have another file that contains the same quantity of information and a
pivot table, but it's only about 200kb. WHY?!?