According to a report (PDF) by PubMatic, display ad rates on ad networks drop slightly in the fourth quarter of 2008. The rate per thousand impressions averaged 26 cents down 3.7 percent from the third quarter. This follows a drop of 21 percent from the second to the third quarter. The rate had a year over year decline of 48 percent. Small sites (under 1 million monthly page views) averaged 61 cents, medium sites (between 1 million and 100 million) averaged 30 cents and large sites (over 100 million) averaged 17 cents. PubMatic compiles its data from a survey comprised of over 5,000 websites, approximately 85% of which are based in the US.