The annual round of price setting for sweeteners is not going so well, Credit Suisse reckons, prompting the Swiss bank to downgrade Tate & Lyle.With sweetener prices expected to be down by around 15%, Credit Suisse (CS) has chopped its earnings forecast for fiscal 2010/11 by £20m for sugar and sweeteners firm Tate & Lyle (T&L).CS’s earnings per share forecast for the Splenda sweetener maker has been trimmed accordingly by 6%.‘With pricing down 15% and raw materials flat, we have lower profits than we were originally expecting,’ explained CS analyst Charlie Mills.Despite downgrading the stock from ‘outperform’ to ‘neutral’, CS has left its price target unchanged at 550p, though it has removed it from its focus list ahead of the T&L trading update on 28 January.