Year	kg per 2015 US$ of GDP
1990	1.1480044315732094
1991	1.0838534900709254
1992	0.6347745691829677
1993	0.537757754338139
1994	0.4980364884778336
1995	0.41132169496504645
1996	0.3802790791555833
1997	0.32085750897702237
1998	0.35968277794888137
1999	0.5270932006583927
2000	0.5260731158334443
2001	0.49305114079116813
2002	0.5486107158680987
2003	0.5717605920957858
2004	0.5660942963437507
2005	0.5083490249597887
2006	0.4783629182697865
2007	0.4708851193725707
2008	0.43300249161564297
2009	0.4347442942840499
2010	0.45924222172410456
2011	0.4807192980041106
2012	0.41910569395497915
2013	0.43811724207170116
2014	0.46572195774450176
2015	0.4212753034036646
2016	0.3887345821690748
2017	0.4425027627179858
2018	0.4185080161154564
2019	0.385056827331948
2020	0.34955163099525444