netmarketshare also tracks users based purely on the user agent, regardless of how much browsing they do. As a result, it skews toward older browsers like IE8 a

netmarketshare also tracks users based purely on the user agent, regardless of how much browsing they do. As a result, it skews toward older browsers like IE8 and IE9 whose users typically don't surf very much at all. IF you track browser usage based purely on page views per browser IE8/9 represent a far lower percentage of all browser usage.