Repsol's hydrocarbons production in 2010 (excluding YPF) was 344,256 barrels of oil equivalent per day, up 3.2% on the figures for 2009. This increase has its origins in Peru, following the start-up of the Peru LNG plant in June 2010; in the United States after the entry into operation of Shenzi in March 2009; in Libya due to increased share, and in Venezuela due to the incorporation of Barúa Motatán, partially offset by the sale of Barrancas, both in February 2010. All of this compensated in part for lower production in Algeria, mainly due to the change in coefficient in 2010, based on the application of the contractual terms; and in Brazil (due to the decline of Albacora Leste).

Isolating the impact of the higher reference prices in Production Sharing Contracts, production would have increased by 6% with respect to 2009.

The extended well test on Brazil's Guará field, in offshore block BM-S-9, began on 25 December 2010 and is expected to last for five months.

As of 31 December 2010, Repsol's proven reserves (excluding YPF), calculated in accordance with the U.S. Securities and Exchange Commission (SEC)'s guidelines, totalled 1,100 million barrels of oil equivalent (Mboe), of which 376 Mboe (34%) relate to crude oil, condensate and liquefied gas and the remaining 724 Mboe (66%) to natural gas.

In 2010, the evolution of the aforementioned reserves was positive, with the incorporation of 165 Mboe most notably from Peru (114 Mboe), Trinidad and Tobago (15 Mboe) and Libya (14 Mboe).

These reserves are mainly located in Trinidad and Tobago (36%). 46% is located in the other South American countries (Venezuela, Peru, Brazil, Ecuador, etc.), 12% are in North Africa (Algeria and Libya), 5% are in the Gulf of Mexico (United States) and about 1% in Spain.

Investments in the Upstream business in 2010 totalled €1.126 billion, maintaining the level of investment from the previous year (€1.122 billion). Investment in development represented 50% of the total and was made mainly in Trinidad and Tobago (16%), Bolivia (14%), Brazil (13%), Peru (12%), United States (10%), Ecuador (9%) and Libya (7%). Investments in exploration represented 38% of total investments and were carried out mostly in Brazil (76%) and the United States (8%).

The agreement signed in October between Repsol and Sinopec for the joint development of exploration and production projects in Brazil entailed a divestment of $4.267 billion (€3.233 billion). The amount of the divestment relates to the percentage of the Group's interest in the liquidity incorporated into the company as a result of the capital increase.

Furthermore, a €70 million down-payment was received in 2010 for the agreed sale of Repsol's 82% stake in the Gaviota underground natural gas storage facility to Enagás, sold for a total of €87 million (of this figure, €16 million are subject to the Ministry of Industry, Tourism and Trade's approval of the enlargement project). This sale, pending definitive approval of the transaction on the part of the competent authorities, is another step in Repsol's strategy of gradual divestment of non-strategic assets.