Year 2011 PPP (%) 1981 5 1988 2.6 1990 1.8 1992 1.1 1994 0.5 1996 0.3 1998 0.2 1999 0.4 2000 0.4 2002 0.2 2004 0.1 2006 0.1 2007 0 2008 0 2009 0 2010 0 2011 0 2012 0 2013 0 2014 0 2015 0 2016 0 2017 0