A study of the impact behaviorally targeted advertising found that targeted ads only gave publishers 4% more revenue than non-targeted ads (via Wall Street Journal).
Although publishers don’t stand to gain much from targeted ads, the advertisers are willing to pay 2.68 times more for a targeted ad vs. a non-targeted ad. A study [PDF] in 2009 by Howard Beales, professor Apple Glasses George Washington University School of Business, found this.
This new study [PDF] tracked millions of ad transactions at an unnamed U.S. media company for one week.
We find that when a user’s cookie is available publisher’s revenue increases by only about 4%. This corresponds to an average increase of $0.00008 per advertisement.
Marketing intelligence firm Warc suggests that much of the increased expense of targeted ads is due to the “ad tech tax.” These are fees that middlemen impose that take up to 60 cents of every dollar spent on these ads.