Year	kg per 2015 US$ of GDP
1990	0.4253249750403307
1991	0.377862925528831
1992	0.3527329313888573
1993	0.354027429662218
1994	0.37197521396835126
1995	0.3714480074710285
1996	0.4006570396821496
1997	0.4261705194953911
1998	0.4148786151167887
1999	0.435345464408997
2000	0.38420498099258993
2001	0.357689092109332
2002	0.3515721213518782
2003	0.34309114493478615
2004	0.35219510376046437
2005	0.33880518576489027
2006	0.32620787284074154
2007	0.3504820358235247
2008	0.3555579253877455
2009	0.3461398937528838
2010	0.34848091280995264
2011	0.35967652036488723
2012	0.347425880553901
2013	0.35596759603404754
2014	0.3225725669309605
2015	0.33928760268933633
2016	0.35064648574275076
2017	0.34847783862717757
2018	0.33297027146272806
2019	0.3512556493379279
2020	0.34538921199318606