Year	kg per 2015 US$ of GDP
1990	0.6901591806519861
1991	0.6905041862377017
1992	0.6814377174054527
1993	0.6820565709131068
1994	0.6902638902848981
1995	0.7036987319286998
1996	0.6982527777071431
1997	0.6987387416296971
1998	0.70284789872062
1999	0.7107613868067242
2000	0.7063128280570106
2001	0.7162203753502964
2002	0.7254067575053013
2003	0.7170059183839619
2004	0.7117145566125385
2005	0.7009634059340561
2006	0.6970605286698919
2007	0.6991694727507318
2008	0.7017403585165867
2009	0.7180902238654556
2010	0.7075155601252935
2011	0.7006666907348725
2012	0.7054498039275503
2013	0.6855902695599775
2014	0.691727219891461
2015	0.6680801125936774
2016	0.6503419821999665
2017	0.6447629536180173
2018	0.6356574193173137
2019	0.6177767111583937
2020	0.5983681235246272