the 6+ numbers that are now released in the PPM markets for public consumption are useless.
We used to complain about the 12+ numbers being garbage, now IMHO the public numbers have very little value.
In the bad old days you could tell when someone wasn't doing well in the ratings.... they were gone after one bad book.
It doesn't matter how many people are listening to any one station. What matters is you have format X catering to demographic Y, who the consultants tell you are the most likely to buy A,B, and C. You have one new kid on the block who just changed to the format, and 2 stations nobody knows exists. Product A,B, and C have manufacturers and retailers who are willing to spend big money to get their message out to demographic Y (also known as your P1). Your job as PD is to put out a product that Joe Blow is going to keep tuned to, so that the sales slugs can go to the makers and sellers of X,Y, and Z can go to them with the super secret book numbers and say "Hey we're KRUD, and we want to be your partner! If you advertise with us, we can make sure that each week 500,000 people are going to hear your spot on our #1 rated morning show that is geared towards the customers you want. How many spots can I put you down for!
Radio is about selling spots and generating revenue. Programming is just the stuff they broadcast between commercials to keep you listening till the next stop set. You could have a station that shows no listeners in the 6+ ratings, but you may have a niche format that a group of people listen to, and you know through research that niche group likes say tofu. You go to every tofu retailer and manufacturer you can find and you convince them you can increase their sales and profits by a small investment in radio advertising. You may have 1000 listeners, but if you can get them to buy Fred's Tofu, and Fred sees his sales go through the roof, he is going to continue buying spots from you, and Fred's competitors are going to want in too, and since there are only so many minutes in the hour, the time becomes more valuable, and Fred and his competition are willing to pay more to get more of it for themselves (to a point). Doesn't matter that there are only a thousand people listening at any given time and you have no ratings, you have proven to Fred that you can deliver customers to him, and he is willing to pay dearly for those prospects.
Look at the "dollar a holler" programs, be they religious, financial, restaurant review, etc. They may get crap ratings, but they have a following that spends(or sends) money. Look at Pat Whitley or the Andleman boys. No doubt their program sucks, just one big infomercial, but even with crap ratings they manage to sell tons of spots and make a pretty good living for themselves. Pat Whitley made so much money off his show, he gave up his regular radio gig to do the food stuff full time.