According to Daniel Druker, VP of marketing at Postini, 94% of all e-mail sent last December was spam.
It's not just the rising volume of spam that's a problem, but the size of the spam messages. Because botnets use stolen bandwidth, spammers can send files of any size at no cost. And that's just what they're doing. In order to defeat content filters that might block their messages, spammers are increasingly using images. The result is that unsolicited bulk e-mail is getting bulkier. The 147% increase in spam that Postini observed in 2006 resulted in a 334% increase in e-mail processing requirement for companies. "This is causing the e-mail infrastructure of many businesses to melt down," says Druker. "Nobody budgeted for four-and-a-half times more infrastructure capacity in one year."
I suspect the other six percent consisted of cute pictures of people's cats. Read it and weep.