Year 2017 PPP (% of population) 1985 0.2 1986 0.2 1987 0.2 1988 0 1989 0 1990 0 1991 0 1992 0 1993 0 1994 0 1995 0 1996 0.2 1997 0 1998 0 1999 0 2000 0 2001 0 2002 0 2003 0.5 2004 0.1 2005 0.1 2006 0 2007 0 2008 0.1 2009 0.2 2010 0.3 2011 0.2 2012 0.3 2013 0.3 2014 0.3 2015 0.7 2016 0.5 2017 0.9 2018 0.7 2019 0.3 2020 0 2021 0.3