At work we use a pair of Cisco Ironport Email Security appliances. In September, only 10% of the email message we received were legitimate. During September, we received over 3.5 million email messages and, of those, only 352 thousand, or 10%, were delivered to staff mail boxes. The rest were spam or contained malicious content and were blocked.
We sent over 194 thousand email messages during the month.
I can’t imagine how we would cope without a spam filter.