Irish cheese maker Glanbia served up a 28.4% drop in half year pre-tax profit while revenue slid nearly 15%.Commenting on the group's performance managing director John Moloney said, "It has been, without doubt, a difficult six months. The sustained downturn in the global economy led to weakening consumer confidence.""In addition, international dairy prices were sharply down on 2008 resulting in a dramatic reduction in dairy product returns and US cheese prices reached historic lows."Profit before tax pre exceptional fell to €38.0m for the half year ended 4 July 2009 from €53.1m before. Revenue fell to €944.9m from €1,106.2m.The board has recommended an increase in the half year dividend to 2.89c from 2.75c before.