It'll depend on your needs.

If you need the excel data embedded in the PPT so you can open the PPT,
doubleclick the Excel object and be able to edit the data, you'll want to do
something like this:

Select the Excel data you want to use and copy it to a new XLS file.  Save that
and copy from there to PPT.  Create a new file for each batch of data you want
to copy.

If you don't need to edit the data later, just copy it into PPT any convenient
way, then when you're sure no more edits will be needed, ungroup it.  That
leaves you with just the text and graphics, no Excel data.

If you want to edit it yourself but don't need others to be able to do so, copy
from Excel then Edit, Paste Special, Link into PPT.  The Excel data remains in
the original XLS file, not in your PPT but as long as you have access to both
files, you can still doubleclick the Excel info in PPT to edit it.

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Steve Rindsberg, PPT MVP
PPT FAQ:  www.pptfaq.com
PPTools:  www.pptools.com
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