AdRelevance data from Jupiter Media Metrix found that top online media companies ran 28 percent of their sites with nonpaid, self-promotional ads. Within that category, entertainment and society Web sites had the highest percentage--30 percent--of self-promotional ads in the fourth quarter of 2000, up 3 percent from the previous quarter. News and information sites climbed 5 percent to fill 22 percent of their sites with "house" ads in the fourth quarter; portals and search engines stayed static at 19 percent.
The report also said that online ads skyrocketed to a record 172 billion-plus impressions during the fourth quarter of 2000. Impressions are the number of times an ad appears online.
The report comes as Internet companies find themselves caught in a slowing online advertising market. Analysts say that Web sites diminish their advertisers' messages by running too many house ads--at a time when they badly need to prove to those advertisers a return on investments.
"House ads can serve a legitimate purpose for media companies, but they need to limit those that are used as mere placeholders," Mike May, research director for Jupiter Media Metrix, said in a statement. " Web publishers should use house ads more strategically, freeing up opportunities for their clients to shine."
Jupiter Media Metrix predicts that by 2005, consumers will encounter an average of 950 online marketing messages for each day spent on the Web. That compares with 610 marketing messages in 2001. May said that the clutter of marketing messages affects the performance of online advertising, and as a result, can cripple Web publishers.