Navigate to Arbitron's Web page (see the Reference section for a link).
Click on the link on the right side of the page marked "Radio Ratings." Fill out the fields of information about yourself, including your name, email address and industry, before continuing to the research page for radio ratings.
Click on the drop-down menu (next to the small "Go" symbol in the middle of the page), and select the major city nearest the market you are researching. Hit the "Enter" key on your keyboard, or click the "Go" symbol.
Determine the estimated number of persons listening to a given radio station by comparing the percentage share listed against the market size. For instance, Radio-Info.com (see Resources) lists the Milwaukee-Racine market at about 1.5 million people. If Arbitron lists WTMJ in that market as receiving 11 percent of the average quarter hour (AQH) share of listeners, then you can estimate that about 165,000 people in this market listen to WTMJ for at least five minutes.