New York—The use of ad networks jumped from 5% of total ad impressions in 2006 to 30% in 2007, a sixfold increase, according to “Digital Pricing Benchmarking Study,” a new report from the Interactive Advertising Bureau and consultancy Bain & Co.

The study was based on an in-depth analysis of proprietary company data, including sales, pricing and impressions across leading online media properties.

Also according to the study, online publisher revenue grew by 32% in 2007 over 2006, and ad network revenue grew by more than 50% during the same time period.

The study also found that the average cost-per-thousand rate for premium video inventory is two to three times that of standard display ads.

“Online publishers are producing more inventory than the market demands, and risk devaluing the premium nature of their brands, particularly in light of ad networks growth and their dramatically lower pricing,” said John Frelinghuysen, partner in Bain’s global media practice and author of the report.