Year	kg per 2015 US$ of GDP
1990	1.4545726102097363
1991	1.4598042709796537
1992	1.389547843391362
1993	1.336475818414344
1994	1.267441872562698
1995	1.2513061251543633
1996	1.1948907508329358
1997	1.1872129167208751
1998	1.146762556709754
1999	1.1451669690003412
2000	1.1316280844715336
2001	1.1135786855318108
2002	1.0957865428454205
2003	1.073286488220942
2004	1.052475713466062
2005	1.0258044503937083
2006	1.0077503322720511
2007	1.0051713208976445
2008	0.9986882823908798
2009	0.9799729165674822
2010	0.9638950732141344
2011	0.9623608608745459
2012	0.9617970663659159
2013	0.9384330598459001
2014	0.934186153006353
2015	0.8882444740798188
2016	0.8681855964663824
2017	0.8571071129228559
2018	0.8545436596747775
2019	0.824012928348668
2020	0.8040770180104451