Year 2017 PPP (% of population) 1997 75.6 1998 83.9 1999 88.4 2000 90.8 2001 85.8 2002 76.9 2003 69.6 2004 70.2 2005 75.3 2006 41.9 2007 32.5 2008 34 2009 33 2010 30.1 2011 27 2012 25.9 2013 21.1 2014 19.9 2015 17.7 2016 17.7 2017 17.5 2018 14.6 2019 14.7 2021 14.4