Average commercial rating does not measure your ad's performance: An alternative approach - exact commercial ratings in buying TV

John Spadaro and Bruce Goerlich
Zenith Media and Rentrak Corporation


Currently, based on the most widely adopted currency, national TV measurement derives from a sample of around 20,000 homes. These ratings are provided by program, based on an average of all national commercial minutes. In a typical hour of broadcast network prime, this represents about 14 minutes of commercials. Because an advertiser usually runs only one 30 second spot, about 96% of the rating does not encompass the advertiser's specific commercial.

On the other hand, with its massive database of over 8,000,000 homes, Rentrak informs an advertiser exactly how many HHs are viewing the commercial.

One barrier in the business of using exact commercial ratings is the worry that they will fluctuate to the point of not being usable for posting purposes; that is, the buyer cannot predict their impact. Rentrak has proven that the massive size of its database gives stability to exact commercial ratings. With the use of exact commercial ratings, Zenith Media is partnering with Rentrak on ECR to obtain that greater level of understanding actual performance on their TV schedules.

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