For the average country station still being rated by diaries this ratio remains quite constant: a little more than one third of diarykeepers account for almost three quarters of average quarter hour audience.
For that reason, radio's research companies have learned that a random probability sample composed of about 60% of a station's "core" (P1/heaviest users) and some 40% of that station's cume as found at random in a metro population provides a reliable indication of how that broadcaster is going to do in the next diary survey.
When PPM started to roll out in the top 50 U.S. and Canada's major markets over the last decade that formula no longer "worked." Many radio stations back when their first PPM ratings were released were unpleasantly surprised to find out that performing extremely well in a traditional perceptual research project fielded with the time-honored sample parameters was no predictor of PPM scores!
Six years ago at the annual December programming "fly-in," Nielsen Audio's clever research crunchers revealed new insights into emerging major market panel samples that still help explain why that may have been happening:
- Unlike in diary measurement where lighter users often fail to report their usage, PPM captures it all, so instead of the vast majority of AQH audience coming from heavy users, it's more of a 50/50 proposition.
- Roughly half of all radio average quarter hour ratings now reflect extremely light, "drive by," perhaps even unintentional use. Those people listen an average of under three minutes per occasion, bringing average "time spent exposed" when down when compared to diary driven data.
- Heavy users (P-1's) are still in the sample, accounting for about half the usage of the average radio station's shares. Their average occasion is ten+ times as long as the other half of the sample, typically something like 35 minutes.
- PPM also shows that those heavy users listen to about twice as many radio stations in an average week that they would have written down, on average, when they filled out a listening diary.
- Savvy programmers and researchers have now had more than six years to fully understand these new dynamics and our ability to project results has been improving, but there is still much to learn, but it's important to keep in mind that actual listening has not changed.
- You can get the about the same number of quarter hours by targeting either group or many more than you did in diaries if you can find a way to bridge the gaps and constantly satisfy both of them.
- Listeners still perceive and make use of radio in the same ways they always have. It's the measurement techniques and the sample that changed, requiring new usage tactics and perceptual-driven strategies.