Television Measurement John Wanamaker said nearly a century ago: "I know that half my advertising dollars are wasted, I just don't know which half." Many people have said that this is more than true in television. While television is only one of the marketing stimuli types employed by marketers, it is the marketing type considered by most advertisers to be their "base medium". In the past 30 years, television has become one of the most difficult media to accurately measure: 30 years ago, the average U.S. television household had access to only 3 or 4 channels, while that figure has grown to over 120 channels today. This number continues to grow with the deployment of digital channels. 30 years ago, reporting was only required on a couple of hundred network television programs each week, while today that number is over 22,000. 30 years ago, only a handful of households were able to change channels without getting up from the couch, whereas today channels can be changed via remote control in virtually every U.S. television household. This has caused a vast increase in channel changing. Today, households can watch television programs from their DVDs, DVRs, VCRs, VOD, or play videogames through their television sets, or access the Internet through their TV sets. Interactive television, already widely deployed overseas, is poised to roll out in the U.S. in a diversity of promising forms involving addressability and personalization. Video on the Web and on Mobile phones are emerging as important new advertising media. Video and digital text displays form part of the burgeoning new field of in-store media. All these promising new media call for a litmus paper system to guide best practices in each new medium.