 A devaluation of the peso in 2002 and a sustained rise in commodity prices since has further encouraged the sector, leading to record production and exports, helping finance record public works spending through export tariffs, a centerpiece of Néstor and Cristina Kirchner's economic policies.These, in turn, became a point of contention when President Cristina Kirchner advanced a hike in export tariffs, leading to the 2008 Argentine government conflict with the agricultural sector; the tariff increase was defeated in the Senate when Vice President Julio Cobos cast an unexpected, tie-breaking vote against the measure.Around 10% of the country is cultivated, while about half of it is used for cattle, sheep and other livestock.