Year	kg per 2015 US$ of GDP
1990	0.3908689028754225
1991	0.3869866741647281
1992	0.415117716636559
1993	0.3513486146541468
1994	0.3893229413615376
1995	0.4344674179079567
1996	0.4960906655980181
1997	0.6051100886733257
1998	0.565701193997636
1999	0.5254158769796237
2000	0.5222062237269756
2001	0.4746252618085092
2002	0.4662364719708935
2003	0.39703807969250077
2004	0.31337390605077925
2005	0.36961526624818614
2006	0.35171970385038487
2007	0.3038551353274975
2008	0.3081206732393684
2009	0.2687142458276188
2010	0.29835812953020174
2011	0.41568366744815405
2012	0.4432034974562383
2013	0.4747134602357287
2014	0.5006675540180526
2015	0.48359081137872834
2016	0.5258682511288453
2017	0.541589884606438
2018	0.5811267158586755
2019	0.5414539275713455
2020	0.4356645552298776