Consolidating from Several Workbooks
 

I am working with several dozen workbooks in Excel. Each workbook is an
income statement for a different company. I would like to have a master
workbook that consolidates or sums each respective cell from the individual
workbooks (files) into the master workbook. The master workbook will have
the same format and structure, but it will pull data from the other workbooks.

What is the best way to do this? I know I can simply use a SUM formula
referencing the workbooks, and that Excel will ask me if I want to update the
links every time I open the master. But I want to be able to automate it so
that I can click a button at any time and the links will update (assuming the
information in the other workbooks will change regularly. Can I create a
button (or Macro) to perform this updating? Also, what is the most effecient
way to perform this task?

I would really appreciate if you could shed some light on this issue. Thanks!