This excerpt taken from the PBR 6-K filed Aug 18, 2009.
Due to the average inventory period of 60 days, international oil and oil product prices, as well as the impact of the exchange rate on imports and government take are not fully reflected in the cost of goods sold in the actual period, but in the subsequent period.
(*) In the quarterly COGS comparison, note that COGS in the 1Q-2009 was negatively impacted by higher unit costs formed in previous periods. This trend was reversed as of the 2Q-2009.
A R$ 500 million reduction in the following operating expenses:
Other operating expenses (R$ 258 million) due to higher gains from fiscal incentives (ADA and Sudene) and reduced losses from the decline in commodity prices and contractual fines;
Exploration costs (R$ 220 million), lower expenses with the write-off of dry or economically unviable wells (R$ 366 million), offset by higher geological and geophysical costs (R$ 144 million);
Selling expenses (R$ 118 million), due to the decline in chartered vessel freight costs, offset by increased sales and promotion costs.
This excerpt taken from the PBR 6-K filed Jun 8, 2009.