This excerpt taken from the PBR 6-K filed Aug 18, 2009.
The main events impacting the year-on-year reduction were:
The reduction in gross profit due to lower international oil prices;
Lower equity income due to losses on investments in the USA from the acquisition of the remaining 50% of the Pasadena refinery.
Higher oil prices and the upturn in sales volume due to the start-up of production in Akpo, in Nigeria, increased gross profit by R$ 189 million.
The constitution of provisions for losses on investments in the USA in the 1Q-2009 also contributed to the improvement.