I'd use uncompressedSize:

#!/usr/bin/perl

use strict;

use Archive::Zip;

foreach my $zipfnm (@ARGV)
{
     if (-e $zipfnm)
     {
          # ZIP file exists.  Proceed.
          my $zipobj = Archive::Zip->new($zipfnm);          # ZIP obje
+ct pointer
          my @mbrhan = $zipobj->members();
          foreach my $mbrhan (@mbrhan)
          {
               # Next member found in ZIP file
               my $mbrfnm = $mbrhan->fileName();
               my $mbrfsz = $mbrhan->uncompressedSize();
               print "$mbrfnm is $mbrfsz bytes\n";
          }
     }
}

exit;

__END__
[download]

D:\PerlMonks>7z l -tzip test.zip

7-Zip [64] 9.20  Copyright (c) 1999-2010 Igor Pavlov  2010-11-18

Listing archive: test.zip

--
Path = test.zip
Type = zip
Physical Size = 330

   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  -----------------
+-------
2015-03-10 15:40:58 ....A           22           22  test.dat
2015-03-10 15:41:09 ....A           28           28  test2.dat
------------------- ----- ------------ ------------  -----------------
+-------
                                    50           50  2 files, 0 folder
+s
D:\PerlMonks>zipgetsize.pl test.zip
test.dat is 22 bytes
test2.dat is 28 bytes

D:\PerlMonks>
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