Shares in printer St Ives slumped by a fifth as it issued yet another profit warning with prices under pressure and margins being squeezed. Total sales for the 39 week period from 2 August 2008 to 1 May 2009 rose by 2.7% but the mix of sales was less beneficial with a higher proprotion of bought-in work, resulting in lower added value. "Overall market conditions continue to be extremely challenging, visibility remains short, prices are under severe pressure and net margins are depressed by under utilisation of capacity," St Ives said, adding that the economic outlook is likely to adversely affect volume and margins, particularly in magazines, exhibition and events and general commercial printing."Consequently, we now expect that the operating results for the year ending 31 July 2009 will fall substantially below market expectations," the statement said.