Media: Did you see the TV revolution?: Channel 4 is 10 years old. Its one-time dreamers are now cash-flow experts. Sue Summers wonders whether grown-up means sold-out

CHANNEL 4 has a fight on its hands. Since 1986, its share of the daytime television audience has almost doubled - from 7.3 per cent to more than 13 per cent so far this year. Far less extra viewing has been picked up during peak hours, when a national network expects to take the bulk of its ratings and advertisement revenue. C4's share after 6pm has risen only from 8.1 to 9.3 per cent in the past six years, little higher than it was in 1988.

That would not matter if the channel could go on relying on joint advertising sales with ITV and a measure of cross-

subsidy. But from the mid-Nineties the umbilical cord will be cut. C4 must thereafter fight ITV, a movie-driven Channel 5 in most regions and perhaps a dozen satellite channels partly or wholly financed by selling their airtime.

In this struggle C4 is fairly well positioned with one-fifth of commercial television viewing, though this nets it only 15 per cent of advertising. Currently this is worth pounds 250m a year: too little to keep the channel in its accustomed style. Expensive strands such as Film on Four have been cut back; worthy but little watched series such as Channel Four Daily and Business Daily have been axed.

When ITV ceases to promote C4 programmes on air, its peak-time audiences may suffer. In any event they will be attacked by a more aggressively populist line-up on the bigger network. For instance, if the proposed third weekly episode of ITV's The Bill plays at 8pm on Monday, Wednesday or Friday, it will clash with Brookside, C4's soap.

Renovating C4's evening programmes means a rethink for three pillars of the schedule since its earliest days.

Brookside's following is no larger than in 1987, and is below Eldorado's. It suffers from inheriting the audience for Channel Four News, an hour of weighty analysis that pulls only 1 million viewers - would the news budget be better spent filling the gap left by ITV's cut in peak-time current affairs? And Film on Four's audience fell from 4 million in the mid-Eighties to 2.1 million in 1991.

Michael Grade knows that we prefer drama serials. Under Jeremy Isaacs, A Woman of Substance attracted C4's record audience of 13.9 million in 1985; other serials from the channel's infancy, Hold the Dream and The Price, scored more highly than recent entries such as The Camomile Lawn and The Manageress. Above all, C4 needs, but has never found, a strong recurrent drama series, an equivalent of Casualty or Minder.

Outside peak time the bandwagon rolls on. The Big Breakfast is winning as many child viewers as TV-am, which is good for toy ads before Christmas. Children also devour C4's cartoons and old US series on Sunday mornings. Somehow it must find more programmes that, when they have grown up, will keep them watching at night.

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