The results, announced by media research company Gfk Media, form part of the first ever national survey to use electronic measurement of radio and TV audiences. The study shows that Radio 1 had a weekly reach of 11.8m adults in the three-month period from September 15 to December 14, the lowest since the survey began publishing results in May.
Radio 1 had been steadily growing its weekly reach in 2003 -- from 12.5m (March 10-May 25) to 13m (June 23-September 14). From that peak, however, it slipped month by month and hit rock bottom with the latest figure, which is 1.2m below the year's high point.
Moyles replaced Sara Cox on the breakfast show in January as the BBC looked to restore the fortunes of its troubled morning outing. Before Cox left, the show had been haemorrhaging listeners.
In contrast to Radio 1, Radio 2 picked up 300,000 more listeners in a month, totalling 15.3m. The news should please presenter Terry Wogan, with whom Moyles had declared war just a few weeks ago.
Radio Five Live was the other big BBC success in the broadcast survey with a reach of 9.44m, adding 350,000 listeners since the previous month's results.
There was good news for electronic measurement's leading proponent Kelvin MacKenzie as the TalkSPORT chief executive saw his station lead the way among the national commercial stations with 6.6m. This was more than 1m listeners over Classic FM's 5.5m and almost 3m more than Virgin 3.7m.
Gfk uses the RadioControl measuring device favoured by MacKenzie. However Rajar, the radio audience measurement body has found inconsistency in electronic measurement tests and will be carrying out further tests this year before committing to them. The Rajar results will be released tomorrow.
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