I've made the same request many times and I still don't get it. My "grassy knoll" theory is that the ratings system is deliberately ambiguous so that anyone can claim to be #1.
The rating system is only ambiguous to folks whom they aren't meant to be of use. The demos and ratings and cumes etc (and the raw data which goes into them) are for the use of the folks who shell out the big bucks to pay for them. Ad agencies, and stations compiling pitches, can feed target data into computer programs and spit out the most, theoretically, efficient buys. What the general public usually sees are the broadscope numbers (like 12+ or 18+) which are fed out to the Haslams of the world who put them into interesting but essentially meaningless 'Mine's bigger than your's" columns which are, to borrow a quote, all sound and fury, signifying nothing. I remember that Wrigley's gum was famous in media circles for being the ONLY 12+ advertising buy in the country.
Plus, the number's don't have to be precise (which would be impossible to produce) but the methodology has only to be consistent to make them useful. Nobody is making ad buys based on Haslam's MediaBiz ramblings or some PD's or talent's statement to the press or listening audience on internet board.
The folks who are paid to know who's Number 1 in a key demo KNOW who's Number 1 in that key demo.
Regards,
TSB