Capital and Heart each spent significant resources promoting their respective breakfast DJs and GfK figures show that, although both DJs increased their audiences, Jono picked up more.
In the four weeks before Vaughan's arrival on April 19, Capital's breakfast show averaged 380,000 listeners a day and Heart averaged 198,000. But in Vaughan's first four weeks, the show increased its audience by 34% to an average of 509,000, while the Coleman show increased by 176% to an average of 546,000.
According to GfK, Heart has also pipped Capital in weekly reach with 2.639m adult listeners -- 1,000 more than Capital.
GfK uses electronic measurement systems to measure radio audiences. It started its broadcast survey in March last year.
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