ISP filters are largely responsible for a decline in e-mail spam, which is expected to continue declining through 2010, according to a report released Friday by Jupiter Research.
Jupiter said the average e-mail consumer received 3,253 spams in 2005, but that number will drop to 1,640 in 2010. The company forecast that the volume of spam messages per consumer will decrease by 13 percent a year until 2010.
Jupiter said spending on e-mail marketing will grow from $885 million in 2005 to $1.1 billion by 2010.
"The next five years will see a more organized e-mail marketing arena," said David Schatsky, senior vice president of research, in a statement. "Delivery rates will rise because of marketers' efforts to improve list management practices. The greater control by ISPs over spam will mean a lot less waste."