A new report from Symantec's MessageLabs finds that short URLs in spam have reached a "historical peak". This type of spam has increased significantly over the past year. Spam containing shortened links hit a one day peak of 18%, or 23.4 billion spam emails, on April 30, 2010, doubling last year's peak levels when spam with shortened links accounted for 9.3% of spam (more than 10 billion spam emails) on July 28, 2009.