Time wasted deleting junk e-mail costs American businesses nearly $22 bln a year. A telephone-based survey of adults who use the Internet found that more than 75% receive spam daily. The average spam messages per day is 18.5 and the average time spent per day deleting them is 2.8 minutes. The loss in productivity is equivalent to $21.6 bln per year at average US wages, according to the National Technology Readiness Survey produced by Rockbridge Associates and the Center for Excellence in Service at Maryland’s business school. 14% of spam recipients actually read messages to see what they say, and 4% of the recipients have bought something advertised through spam within the past year.