3. Petroleo Brasileiro ( PBR) is an integrated Brazilian oil and gas company operating in segments like exploration and production, refining, transportation, and marketing of gas and power. Higher crude oil prices and volumes during the year buoyed the company's exploration and production segments, while downstream was negatively affected. For the first quarter of 2011, net income increased 42%, boosted by a 7% uptick in domestic sales, led by jet fuel, natural gas, and diesel. Petrobras' estimated oil reserves stand at about 11 billion to 12 billion barrels of oil equivalent (boe) with a production output of more than 2 million boe per day. The recent acquisition of Libra oil field in the Santos Basin would sustain a higher replacement ratio of 144%, in comparison to peers. Exploration and production capex stood at $9.2 billion for the quarter, primarily expanding oil and natural gas capacity in the pre-salt areas. The stock is currently trading at 9.6 times its estimated 2011 earnings. Going forward, on average, analysts expect the stock to deliver 47% during the next one year.