Haiti has a predominantly free market economy, with a GDP of $19.97 billion and per capita GDP of $1,800 (2017 estimates). The country uses the Haitian gourde as its currency. Despite its tourism industry, Haiti is one of the poorest countries in the Americas, with corruption, political instability, poor infrastructure, lack of health care and lack of education cited as the main causes. Unemployment is high and many Haitians seek to emigrate. Trade declined dramatically after the 2010 earthquake and subsequent outbreak of cholera, with the country's purchasing power parity GDP falling by 8% (from US$12.15 billion to US$11.18 billion). Haiti ranked 145 of 182 countries in the 2010 United Nations Human Development Index, with 57.3% of the population being deprived in at least three of the HDI's poverty measures.