Exactly what benefit do advertisers get from ratings taken from PPM technology that registers that the station is on even if the people aren't listening to it? WCBS-FM, which is being played in the background like wallpaper in various businesses, gets to charge more per spot by having artificially higher ratings because of PPM technology. The advertisers pay higher rates but, get no benefit if the station is on but, nobody is listening. The smarter thing for advertisers is to do some kind of recall market research that gives some kind of statistical data on stations where the ratings come from actual listening and not just being on in the background. The better buy for advertisers might be a lower rated station where the audience is actually listening using PPM technology rather than paying rates based on PPM technology where the station is on but, there is no guarantee that anyone is listening. The bottom line is that with PPM technology, a station such as WCBS-FM has inflated ratings when in reality, the amount of people actually listening at any time is much lower. PPM is just as inaccurate in its own way as diaries.