1. U.S.
Share of malicious computer activity: 23%
Malicious code rank: 1
Spam zombies rank: 3
Phishing Web site hosts rank: 1
Bot rank: 2
Attack origin rank: 1
In 2008, the average cost per incident of a data breach in the U.S. was $6.7 million, a 5% increase from a year earlier, according to the Ponemon Institute.
