Year 2017 PPP (% of population) 1970 0 1975 0.2 1979 0.2 1984 0.5 1990 0.2 1996 0.2 1997 0.2 1998 0 1999 0 2000 0 2001 0 2002 0 2003 0.2 2004 0 2005 0 2006 0 2007 0 2008 0 2009 0 2010 0.1 2011 0 2012 0.1 2013 0.1 2014 0 2015 0.1 2016 0.1 2017 0 2018 0 2019 0.1 2020 0.1 2021 0.1