Capital attributed the falls to difficult advertising marketing conditions, although it said that it was encouraged by recent signs of optimism in the media market place. Revenue fell by 3.9% over the 12 months ending September 30 to £115.3m.
Last month's Rajar figures revealed that Capital FM in London had lost audience share and was overtaken by Heart FM. Capital Radio said that it had already instituted structural, management and programming changes to tackle declining audiences.
David Mansfield, chief executive of Capital Radio, said: "We are confident that the management and programming changes at 95.8 Capital FM will reclaim listening hours in the long term."
The station is gambling on Johnny Vaughan, a veteran of television presenting but a newcomer to radio, to maintain Capital's breakfast audience when long-time presenter Chris Tarrant hangs up his headphones next April.
Looking ahead, Capital said that there were indications that booking levels for December were on the up, meaning that the company will have recorded six consecutive months of growth.
Mansfield said: "With greater visibility and positive revenue forecasts for the current quarter, we remain cautiously optimistic of early signs of an improvement in the advertising market as a whole."
Outside London, Fox, Invicta, Power, Red Dragon and Southern have maintained market leadership, with BRMB in Birmingham improving its performance. Century FM saw revenue growth rise, and London new-music station Xfm was moving from a niche market to having a broader listening base, Capital said.
Shares in the company leapt this morning by 6.5%, rising 28p to trade at 460p.
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