Very long-term persistent cookies are 6 times more common on Windows-based websites than on Unix-based sites.

High traffic sites tend to use cookies that expire in years or decades, whereas low traffic sites prefer shorter expiry periods.

94.3% of vBulletin sites use HttpOnly cookies, compared to less than 3% of WordPress, Joomla and Drupal sites.

Top 1,000 sites are more than 6 times as likely than average sites to use cookies that expire after more than 10 years.

IIS based servers are 4 times as likely to use HttpOnly cookies than Apache based servers.

Top 1,000 sites are more than twice as likely to use persistent cookies than average sites: usage of persistent cookies broken down by ranking.