Shares in Britvic fell back after private equity group Permira sold its 14% stake in the soft drinks maker.Permira, which invests in sectors such as consumer products and media, bought into Britvic in December 2006.Last week, Britvic, which makes Tango and distributes Pepsi and 7UP in the UK, said it saw pre-tax profits in the half year to 12 April rise by 16.3% from the same period a year ago to £20m, as revenues climbed by 6.3% to £483.2m.UK carbonates were the main growth-driver, with revenues from the division climbing by 10.2% to £204.4m. This helped to offset a poor performance in struggling Ireland, where operating profit fell to nil from £4.3m as revenues remained pretty much flat at £101.m.