A sea change is imminent in the buying and selling of US television airtime. Nielsen Media Research says it will supply national commercial ratings from this fall based on live viewership plus seven days of recorded DVR playback viewing.

After a year to analyze the data, TV networks and media agencies could begin to use these ratings as the currency of advertising. Presently - and for the immediate future - ad rates are based on live program audience figures.

Despite the networks' best efforts during the latest upfront sales, media buyers have refused to pay a proposed premium for those viewers who watch on digital video recorders [WAMN: 07-Jun-06].

Comments Lyle Schwartz, broadcast director and managing partner at Mediaedge:cia, which first mooted the idea that Nielsen should supply commercial ratings: "It is something we feel is necessary in order to fully analyze the value of delayed viewing."

He adds: "The important thing is Nielsen is now producing the data so that we can analyze the economic impact in the marketplace. We are definitely making progress."

Data sourced from Adweek (USA); additional content by WARC staff