Excel 2002 files up to 78% smaller after installing XP SP3. *What*the?

[Jim Luedke]

I'm running Office XP in Win 2000. I hadn't installed any XP Service
Packs, so I just updated to XP SP3.

I have a couple of large (multi-MB) Excel 2002 workbooks. On saving
them for the first time after the update, the size of one .xls shrank
78%, that is, to only **22%** of what it was before. The other shrank
by 26%, to 74% its prior size.

I mean, WHAT the?

What I suspect is: My two files have a lot of VBA code and:

1) Even tho' they're much smaller now, no data or code seems to be
lost.

2) Before, I noticed that adding even a little code greatly increased
file size.

3) Conversely, whenever I deleted old procedures, Excel wrongly
retained them somewhere--because on retyping their names, the VB
Editor wrongly auto-capitalized them as if they still existed.

4) I always had a gut feeling that file sizes were somewhat out of
proportion to their content.

5) Conversely, after the SP3 update I loaded and saved a large
workbook that has only minimal VBA code. Its file size didn't shrink
at all.

Is this apparent SP3 (or SP2 or SP1?) trash-collection bug fix known
to you all?

Thanks.

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