2000/2001
“In the third quarter of 2000, online advertising shrank overall for the first time, dropping 6.5 percent, to just under $2 billion dollars. The average price of a banner ad toppled from a $50 CPM to less than $5.”
MediaPost
2001
“CPM = $10 (a typical rate for general, not-very-targeted websites)”
WilsonWeb
“The general consensus seems to be that the average effective banner ad CPM today is somewhere in the neighborhood of $10.”
Content Intelligence
2002
“Today, you can buy a run-of-network banner for $2 CPM or less”
Clickz
2003
“CPMs (cost per thousand impressions) have sort of found the bottom’ said Gary Stein, an analyst with Jupiter Research. The average Internet CPM is now $1.13–down from a year-2000 norm of $4 or $5, and when some very targeted sites enjoyed as much as a fat $100 per CPM. ”
AllBusiness
2004
“As of 2004, prices range from $1/CPM for a run-of-network to about $50/CPM or more for specialized targeted runs”
Wikipedia
2005
Fifty-five percent saw prices rise for run-of-network inventory, even though as much as half of available inventory on larger networks such as Yahoo! remains unsold, or goes for as little as $1 to $3 CPM
Media Buyer Planner
2006/2007
Judging by the conversations I’ve had with various publishers and agencies I’ve been communicating with over the last 12 months,- prices average have been anywhere from 20c for very untargeted space, e.g. general social networks; to $20 CPM (and higher in some cases) for highly targeted, top shelf sites