[illuminati tmp]$ gunzip --list /tmp/xyz.tar.gz 
  compressed uncompressed  ratio uncompressed_name
       36603       337920  89.1% /tmp/xyz.tar
[illuminati tmp]$ gunzip --list /tmp/xyz.tar.gz 
  compressed uncompressed  ratio uncompressed_name
      144764      1331200  89.1% /tmp/xyz.tar