Keep a static record of data
 

Dear reader,

I have a data set that refreshes to an Excel spreadsheet. I want to be able
to track changes of this data set from one week to another. In order to do
this, I need to have a static record of the data on a weekly basis. Is there
a way to automatically paste special the value of a dataset according to a
date?

(I know this task is easily accomplished in Access. Don't ask me why I'm
doing it in Excel...)

Thanks for your help,

Pablo