According to the Radicati Group, there are about 684 mln email users worldwide, with nearly 1.2 bln active email accounts. Worldwide email traffic per day totals about 136 bln messages, of which 64% are spam. Over 61% of worldwide email mailboxes are delivered through a webmail service provider or ISP. Mobile phone mailboxes currently account for only 3% of worldwide active mailboxes, but this market segment is expected to grow rapidly over the next 4 years. Revenue in e-mail archiving market is expected to grow at an average annual rate of 80% over the next 4 years, totaling over $6.2 bln in 2009. Growth will also be strong in the corporate anti-spyware market, where revenue will increase at an average annual rate of 84% over the next 4 years.