The extreme poverty rate has declined significantly between 1999 and 2010. In 2001, it was estimated at 40% of the population, while by 2011 the figure dropped to 17.4% of the total population. This is explained to an extent by emigration and the economic stability achieved after adopting the U.S. dollar as official means of transaction (before 2000, the Ecuadorian ''sucre'' was prone to rampant inflation). However, starting in 2008, with the bad economic performance of the nations where most Ecuadorian emigrants work, the reduction of poverty has been realized through social spending, mainly in education and health.