debts of nearly US$9 billion. The book value of YPF was US$4.4 billion at the end of 2011; its total market capitalization on the day of the announcement was US$10.4 billion. Repsol officials submitted the matter to the World Bank ICISD for arbitration. The Argentine government and Repsol reached agreement in principle on compensation in November 2013, and on 25 February 2014, Repsol announced final agreement that the Argentine government would provide Repsol with guaranteed Argentine government bonds of varying maturities, the nominal amount varying to assure that Repsol would in fact receive US$5 billion in compensation for the 51% of YPF nationalized. YPF also acquired a controlling stake in Metrogas (the nation's largest gas distributor) in November 2012. A joint exploratory venture for the development of tight oil and shale gas at the Vaca Muerta field was signed with Chevron Corporation on 16 July 2013. Following its renationalization, rapidly rising investment levels at YPF have been funded mostly via internal financing, by Chevron, and by the periodic issuance of high-yield corporate bonds. These bond issuances were raised to US$1.5 billion per series in April 2015, as demand surged to US$4 billion. In December 2019, the recently inaugurated President Alberto Fernández put Guillermo Nielsen in charge of YPF. Nielsen was replaced by Pablo Gerardo González in January 2021. Operations The company remained the largest in its sector in Argentina despite declining production, operating 52% of the nation's refinery capacity in three facilities and 1,600 filling stations. Its sales of gasoline and other motor fuels totaled 12.15 billion liters (3.21 billion gallons) in 2011, 57% of the national market in these. Oil production in Argentina peaked in 1998 at 308 million barrels and declined steadily afterward, reaching 209 million in 2011. Natural gas production also declined, from 52 billion m³ in 2004 to 45.5 billion. The company's production of oil had fallen by 43% between 1998 and 2011, and of natural gas by 37% from its high in 2004. Oil exploration fell from 30 wells in 1998 to 8 in 2010 (French energy firm Total S.A. overtook YPF as the leading oil driller in Argentina). YPF shares of total output fell 8 points to 34% in oil, and 12 points to 23% in natural gas; its declines in output represented 54% of lost oil production and 97% in the case of natural gas. The company's oil production had declined by a