Adults-per-set

Adults per set (literally: "adults per set") is a historical metric used in television audience research to estimate the average number of adult viewers present in front of each television set turned on at a given time. Along with similar metrics such as "Viewers per set" or "Children per set," it served to translate the figure for households with TVs on (Households Using Television - HUT) into an estimate of the actual number of individuals exposed to a program or advertisement.

2. What is it for / Why is it important

In an era when television viewing was predominantly family-based and concentrated on a single household device, this metric was crucial for media planners and advertisers. It allowed them to go beyond simply counting the "homes tuned in" to quantify, albeit with an estimate, the true size of the audience in terms of individuals. Its importance lay in its ability to more accurately assess the potential of an advertising campaign.

3. When to use it / In what context is it useful?

This term was commonly used in the early stages of television media planning, from the 1950s to the 1980s. It was calculated through listening diaries compiled by sample households or through telephone interviews. Today, it is a largely obsolete concept, replaced by much more sophisticated and individualized measurement methodologies (such as Auditel meters) that track the listening of individual people in the room.

4. Practical example

Let's say that during a certain time slot, searches indicated an "Adults-per-set" value of 1.5. If 1 million households were watching a particular program at that time, the media planner could estimate that the audience for that program was approximately 1.5 million adults (1,000,000 households x 1.5 adults/household). This data was then used to calculate the cost per contact (CPT or CPM).