Year 2011 PPP (%) 1998 2.7 1999 2.6 2000 1.7 2001 0.7 2002 0.5 2003 0.3 2004 0.1 2005 0.1 2006 0 2007 0 2008 0 2009 0 2010 0 2011 0 2012 0 2013 0 2014 0 2015 0 2016 0 2017 0