Year kg per PPP $ of GDP 1990 0.34863539844102276 1991 0.35327039498900525 1992 0.3544824646522028 1993 0.3421734121298736 1994 0.3202906509717343 1995 0.337408640848525 1996 0.3562620475596666 1997 0.31746057872920813 1998 0.34832264355437575 1999 0.355818874607004 2000 0.35768026727151564 2001 0.3507009959637024 2002 0.3311632481515935 2003 0.3432665235548974 2004 0.31417779688199626 2005 0.29508881428325684 2006 0.26432719468082616 2007 0.2206227893504027 2008 0.2388754889169162 2009 0.23417962975142176 2010 0.2390554399142557 2011 0.21928385682087417 2012 0.20747271213609605 2013 0.2087673563653272 2014 0.20288405784059013 2015 0.2094504088873393 2016 0.21713614345975077 2017 0.16746750441714459 2018 0.14997984821924018 2019 0.145828945035404 2020 0.15937748703277274