Year kg per PPP $ of GDP 1990 1.4737578928854491 1991 1.4649730456006531 1992 1.4760488587857044 1993 1.3902874273751369 1994 1.3486485934090944 1995 1.2915758590506563 1996 1.2317749873282064 1997 1.1177281197097677 1998 1.1724712604784855 1999 1.1212329629906639 2000 1.0329843715939608 2001 0.9760734725903656 2002 0.918192016754141 2003 0.8755877467031805 2004 0.7845709806291737 2005 0.7087586569675857 2006 0.6234752703086678 2007 0.5675728196819708 2008 0.5013676923814162 2009 0.4737811796767589 2010 0.46226629335416924 2011 0.4387224695045357 2012 0.40728023125347845 2013 0.3713420553855271 2014 0.34970751897108965 2015 0.3443360054758316 2016 0.33753223280286676 2017 0.3235009762062026 2018 0.3082916800918726 2019 0.2840812302308719 2020 0.2690959710805158