Year 2017 PPP (%) 1979 0.2 1986 0.3 1992 0.1 1997 0.4 2001 0.2 2002 0.6 2003 0.6 2004 0.6 2005 0.6 2006 0.3 2007 0.4 2008 0.5 2009 0.5 2010 0.4 2011 0.3 2012 0.5 2013 0.4 2014 0.4 2015 0.4 2016 0.3 2017 0.4 2018 0.4 2019 0.6 2020 0.5 2021 0.4