In 1978.. half of all radio listening was on the AM dial. By 2011 AM listenership had fallen to 15 percent, or an average of 3.1 million people, according to a survey by Veronis Suhler Stevenson, a private investment firm. While the number of FM listeners has declined, too, they still averaged 18 million in 2011.
Although five of the top 10 radio stations in the country, as measured by advertising dollars, are AM — among them WCBS in New York and KFI in Los Angeles — the wealth drops rapidly after that.
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