sentences:  As secretary, Carstens took the unconventional decision to hedge Mexico's oil earnings for 2009 against possible price falls, leading to an $8 billion profit for the country.In the aftermath of the 2007 popular protests against rising food prices, Carstens regarded high food prices as a positive driver for investment in agriculture.Carstens was nominated to the Bank of Mexico on 9 December 2009 by President Felipe Calderón, replacing 12-year veteran Guillermo Ortiz, who reduced inflation from double digits to 4 percent by the end of 2009.