At its peak, in June 2009, the figure was 90.4 percent, with a shocking 5.7 trillion of the 6.3 trillion emails sent being spam.
The number has been ticking down for months, and was as high as 52.1 percent in April.
Symantec attributed the decline to the increase in legal prosecution against botnets, improved spam filters and blockers and faster reaction times by network providers.
Here is the full security report:












