Radicati: Spam statistics

A recent study by the Radicati Group Inc., a research firm in Palo Alto, Calif., found that spam accounts for 14.5 billion messages a day - or 45 percent of all e-mails - and costs businesses globally $20.5 billion a year in lost productivity and technology expenses.

The future is even bleaker, according to the firm: It predicts that 58 billion junk e-mails will be sent every day within four years, costing businesses $198 billion annually.

Radicati estimates that spam costs businesses an average of $49 per mailbox this year but forecasts that could rise to $257 per year by 2007 if nothing is done to curtail the proliferation of junk messages.