I am currently building a workbook with multiple pages which tie data
between various tabs within the same workbook. There are a number of
interations that the data is going through; however, there are no pivot
tables, no references to other workbooks, and 2 very small macros. However,
the file size recently jumped from 5meg to 10meg.. and then again from 10meg
to 30meg.

Any ideas on what could have caused the problem?

Currently, I am reworking some of my equations early on in the data
processing, so there are a number of #ref errors on later pages. Could this
be why?