Ranked fifth in the Index of Economic Freedom (2017), Australia is the world's 13th largest economy and has the tenth highest per capita GDP (nominal) at US$55,692. The country was ranked third in the United Nations 2017 Human Development Index. Melbourne reached top spot for the fourth year in a row on ''The Economist''s 2014 list of the world's most liveable cities, followed by Adelaide, Sydney, and Perth in the fifth, seventh, and ninth places respectively. Total government debt in Australia is about A$190 billion—20% of GDP in 2010. Australia has among the highest house prices and some of the highest household debt levels in the world.