I am generating a tex file that has a variable length table for each quarter of the year. I would like to keep the tables centered under one another unless there is not enough room for the table, in which case I would like to start another page. I am using the letter doc style but when I get a table that won't fit on the page is places it on the right had side of the columns on the same page. I would like to get it on a new page instead. I have tried using minipage but without success.
Your 7 KB example.tex is not what we understand as a minimal example (and public.me.com didn't like my browser).
It is full of custom macro definitions, which one has to understand to solve your problem.
After quite some reading (and jumping around in your file), I think I found the origin of your problem:
This is called after the summary lines, if there were enough lines before the last header line.
So, in effect your
There is no space between them, which means, those two minipages will be put on the same horizontal line. Changing the
(This inserts a space at this point, leading to a possible line break.)