According to Britvic's annual soft-drinks report, Coca-Cola, whose brands include Coke and Fanta, saw a 7% drop in sales to £1.46bn, while those for Britvic, the second-biggest manufacturer, fell by 3% to £615m.
Coca-Cola's troubles were compounded by the poor performance of its top-selling take-home brand, Coke, which lost £4m, or 3%, from its sales. Fanta sales fell by 11% to £162m.
Sales of Britvic's Tango range were down 19%, despite being backed by a £3.3m media spend.
The fall in fizzy drinks sales was balanced by a bonanza for 'healthy' drinks in sectors such as pure juice and water.
Danone was the year's strongest mover. Its Actimel product grew by 20% to £287m, making it the fourth-biggest brand. Volvic and Evian, the two leading water brands, grew by 12% and 4% respectively.
The figures were compiled by Britvic and ACNielsen Scantrack Impulse Data. Britvic claims that its figures cannot be compared to previous years' reports because of slightly different samples.
CCE declined to comment.
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