Year 2017 PPP (%) 1995 31.6 1996 30.6 1997 30 1998 29.2 1999 28.4 2000 28.2 2001 27.5 2002 27.6 2003 26.4 2004 24.5 2005 23.4 2006 22.4 2007 21.4 2008 20.1 2009 20.4 2010 19.1 2011 18.3 2012 17.5 2013 17.1 2014 16.8 2015 17.3 2016 17.5 2017 17.7