Sophos has produced its latest report on the top twelve spam relaying countries over the third quarter of 2006. As the chart below shows, the US is by far the largest spam relay with almost 1/4 of all the world’s spam originating from the US computers. Some experts believe this lead is due to the emergence of over 300 strains of the mass-spammed Stratio worm.

Top Twelve Spam Relaying Countries in July-September 2006 Chart