Sugar prices at mill gates have declined by as much as 5.5 per cent in the past one month due to subdued domestic and export demand, with some grades of the sweetener trading at the government-set minimum selling price of Rs 29 a kg on Wednesday. "Price of the S-30 grade sugar has fallen to Rs 29 per kg in Maharashtra this week as demand is tepid. Prices were ruling high before Diwali due to festival season demand," said Ashok Jain, president of the Bombay Sugar Merchants' Association.