Year	kg per 2015 US$ of GDP
1990	0.652626387900181
1991	0.645753774149089
1992	0.6595236949798878
1993	0.6921560985961559
1994	0.7110428703540085
1995	0.7133411162989988
1996	0.7061778204185047
1997	0.7057257459112019
1998	0.6767918598468075
1999	0.6733949513317297
2000	0.6581128270435611
2001	0.6829511588543099
2002	0.7015114547495344
2003	0.6892258377159177
2004	0.6671436342664573
2005	0.6758030953086659
2006	0.6704248339723045
2007	0.6679194852319251
2008	0.6838723142681556
2009	0.703839823466519
2010	0.711461355162135
2011	0.7020255746222149
2012	0.7141030512490033
2013	0.7101444084367134
2014	0.7178967188293701
2015	0.7111046351891015
2016	0.6933277038135511
2017	0.6888519202625898
2018	0.6650970666775782
2019	0.6611477962461583
2020	0.6683040422598644