(Lance Whitney, CNet) Spam accounted for 95% of all email sent worldwide during the third quarter, according to a report released today.

Panda Security's third-quarter report also found that 50% of all spam came from 10 countries, with India, Brazil, and Russia as the top three sources. The U.S. came in No. 8, while the U.K. dropped off the list. Much of the spam that invades in-boxes comes from botnets that hijack computers whose owners don't realize their PCs have been infected, the report noted.

Trojans now are responsible for 55% of all malware threats, with many of them designed to steal information in order to access financial accounts. These types of threats have generally grown over the past two years, according to Panda, because their creators know they can get the greatest return on investment.