1. the hits you're sending out are not unique, and his script only displays uniques.
and/or
2. you're being attacked by a hitbot/file leecher and you should deny these IPs in your .htaccess to keep them from fucking up your trades.
If it's #2, you better do something about it, because it will kill your site. Look for high #'s in/out in repetitive IPs, especially in the nocookie stats. Go here to learn how to block them...
http://www.javascriptkit.com/howto/htaccess5.shtml