Almost 90% of emails are spam, while its size is shrinking, reducing especially those messages with attachments. Symantec has released its Message-Labs Intelligence monthly report which announces diver safety-related data and the amount of spam generated worldwide. As shown in the study during the month of February there has been an increase in spam reaching 89.4% of all email generated. This is 5.5% higher than found during the month of January this year. Symantec attributes this growth to increased activity of Grum and Rustock Bot Nets, especially the former, only the month of February has increased by 51% and generates 26% of total spam traffic.

As for types of messages, the report shows that pharmaceutical copan offers 65% of all spam. Moreover, the tendency of these messages is to reduce its size. This is the case of images, increasingly embedded in emails themselves but linked to external servers. This is because this way the creators have more control over active email accounts and also can generate more spam in less time. In this regard it is essential to configure mail clients to not display images by default. Of the 5 Kbytes per average spam message in October 2009 has gone to 3.3 Kbytes in February 2010. Finally, only 0.56% of these messages contains a file attachment.