IDC estimates that spam comprises about 38% of all e-mails sent in 2004 in North America, up 2% YTY. In 2002 spam comprised 24% of North American traffic. 31 billion e-mails are sent daily, according to IDC. The number of spam sent on an average day is 11 bln, compared with 4.5 bln in 2002. In comparison, the number of person-to-person emails currently sent each day and in 2002 is 12 bln and 10.5 bln, respectively.