Year	kg per 2015 US$ of GDP
1990	0.8556510089230982
1991	0.8767200799674301
1992	0.901718793932018
1993	0.9508285223431256
1994	1.0107300040441374
1995	1.0190068460642383
1996	0.9844812943831642
1997	1.0003728243529912
1998	0.9221305239163841
1999	0.9164848009415952
2000	0.9051703884905073
2001	0.9240940904859481
2002	0.9144672246509032
2003	0.9213840211997865
2004	0.9098280079004811
2005	0.9381259448651664
2006	0.9345845255001604
2007	0.9161066605020606
2008	0.9180480375590916
2009	0.9282200669989195
2010	0.8986591149275636
2011	0.912961665602992
2012	0.9237881039936243
2013	0.9412759292296741
2014	0.9469019469934742
2015	0.9330884619582736
2016	0.8970077029500108
2017	0.9045527304099178
2018	0.9056188071300104
2019	0.8894890323180269
2020	0.8854012024450896