Compressed file size is bigger then uncompressed file size on cluster

Hello,

I noticed the following problem on a windows 2000 cluster.
If I compress all the of a certain user, the size is 25,5
MB, while the uncompressed size was 24,6 MB !
This does not seem to much of a problem, but the higher
the amount of files, and the kind of files involved, the
bigger the difference.
The check is done from Windows Explorer, properties, mark
compress files and subfolder on and off.
Any suggestions ?

Thanks in advance,
J.Kulk