Year kg per 2021 PPP $ of GDP 1990 0.283671758127453 1991 0.29454414002066215 1992 0.3026500969688632 1993 0.3186245716135705 1994 0.33916813892813724 1995 0.3411218277837166 1996 0.3295424788817996 1997 0.3342374551532811 1998 0.3068347658233526 1999 0.3039665430567598 2000 0.3001009491544479 2001 0.30637479991492605 2002 0.3036468566244286 2003 0.30704386943531353 2004 0.3027309320732428 2005 0.3126175599979252 2006 0.31106400170534615 2007 0.30466812393844733 2008 0.3042762907941848 2009 0.30690058369944545 2010 0.29748627237131975 2011 0.2963678399775744 2012 0.30320840465382365 2013 0.3082517356831884 2014 0.3085750164737116 2015 0.29958564759794687 2016 0.28674958013022045 2017 0.289476607402438 2018 0.2889954442546562 2019 0.28212447565605236 2020 0.2762175937378167