THE maximum pre-tax price of a 12.5 kilo bottle of butane gas will be 11.78 euros from January 1, an increase of just one euro cent over the price in force since October, which was 11.77 euros. Prices are revised automatically every three months, taking into account the increase in the cost of the raw material, freight charges and the exchange rate between the euro and the dollar. The new price has been set by the ministry of industry, tourism and commerce. According to the formula for calculating the price, the new cost of butane and propane in containers of more than eight kilos will be 81.2474 cents per kilo, plus 16 percent IVA. The cost of the raw material has gone up from $494.05 to $506.12 a ton, an increase of 2.44 per cent. Freight charges dropped by 4.18 per cent from $63.8 to $61.2 per ton. Over the last three months, the euro has appreciated 1.54 per cent with respect to the dollar.