I know and didn't realize a share was so small, compared with cume but if you had what amounted to 4000 people in half a share, that could be considered, "many" in small towns. What I didn't know was that the total share was only 8% of the total population above 6.
But 4,000 AQH listeners in Blyth would be a share of 100.
In an area as big as Los Angeles, an AQH that low means that very few listeners live in an area near an advertiser's location or offices. And it's only small advertisers that are going to buy a low rated station.
In other words, nobody will drive from Sylmar to Culver City to respond to an ad. It is more than an hour driving, at best, each way. And there are not enough listeners in any area to make the advertising "work".