Year	kg per 2015 US$ of GDP
1990	0.9647063777857477
1991	1.01038161293195
1992	0.9935305561130556
1993	0.9961487619147562
1994	0.9896985762569258
1995	0.9992984506228847
1996	0.9831359608171816
1997	1.002690486024638
1998	0.9695645257753307
1999	0.9734165788978484
2000	0.969522285632044
2001	0.9483089883117752
2002	0.9446671403690724
2003	0.9066465575491995
2004	0.9070488402716579
2005	0.8822229682924904
2006	0.8766496646143054
2007	0.8993515649153301
2008	0.9199565410160101
2009	0.9398667377645389
2010	0.9243847383007657
2011	0.9305712797433496
2012	0.9545105009875563
2013	0.9278636005807355
2014	0.9431507035863325
2015	0.8904673704691476
2016	0.8497014315438793
2017	0.8427908354295994
2018	0.8368005448092387
2019	0.7938488582782356
2020	0.761184610095724