Every week, 2,985,400 adult consumers tune-in to a Detroit radio station. That is way more than are reached by other media, including local television, newspaper, social media, or streaming audio sites like Pandora and Spotify.

A more significant number for thousands of Southeast Michigan small business owners who advertise on Detroit radio is how many of these listeners stick around when their commercials come on.

A 2011 Nielsen study discovered that, on average, 93% of listeners stayed with the radio station they are tuned-to when the commercials come on. That number amazed many advertisers at the time who believed that audiences were far more likely to defect when the music stopped.

A lot has changed since 2011. Metro Detroit consumers have many more media options and can instantly connect to each  with a button-push, mouse-click, screen-tap, or voice command. With all of these choices, do radio audiences still stay tuned during commercial breaks?

If you were one of the 2,985,400 adult consumers who listened to  the radio in Southeast Michigan last week, then odds are you heard a commercial for the Law Office of D. Todd Williams. The firm specializes in criminal defense cases involving traffic violations, probation matters, expungements, and serious felonies.

Mr. Williams has been advertising on Detroit radio every single month for the past 23 years.

"Radio advertising has been critical to building my practice," he says. "I can tell the days when my commercials run because those are the days my phones ring."

Shortly after passing the bar exam in 1995, Mr. Williams opened his firm operating from the basement of his Rochester Hills townhouse.

Mr. Williams's first cases came from friends and their referrals.

"Our franchisees love advertising on Detroit radio," says Katherine Villeneuve, Director of Marketing & Franchise Support for Auto-Lab. "They understand that radio reaches the masses, and can achieve the messaging frequency to be effective."

Auto-Lab started in 1989 as a single-independent store in Sturgis, Michigan. The company has expanded to include 21 franchises across the country. Nine of the stores are located in Metro Detroit, each operated by a local, small business owner.

Auto-Lab offers consumers the same diagnostic, maintenance, repairs, and parts as a car dealership's service department but, for what Ms. Villeneuve describes as a 'fair price'.

To drive traffic into one of Auto-Lab stores in Southeast Michigan, each franchisee contributes 3% of their gross sales to a cooperative marketing fund. Ms. Villeneuve then works with the owners to create persuasive, annual advertising campaigns.

"Each of the owners has input into how the money is spent," she says. "Afterall, because they are in the stores every day, they have the best sense who their customers are."

For the last four years, the Metro Detroit Auto-Lab owners have chosen advertising on Detroit radio as the primary way to reach new customers.

"Our phones started ringing even before our first commercial on Detroit radio ended," says Dr. Kairi Horsley, DPM.  He and his father, Dr. Barton Horsley are co-owners of Horsley Foot and Ankle, a podiatric medical practice in Southfield.

"That was, in 2015," says the younger Dr. Horsley. "Five years later, our commercials still bring us 12 or 13 new patients every week."

Before 2015, the Horsely's had been no stranger to the power of radio. 

When Dr. Kairi joined the practice after his medical residency at the Michigan Surgical Hospital, the two Horsley's teamed up to purchase time for their own talk show on AM radio. During their program, the doctors would discuss prevention and care for the pathologies and diseases concerning the feet.

"We were finding enough new patients from the show, so we weren't losing money," says Dr. Kairi. "But, I kept thinking there could be a better way."