Year	kg per 2015 US$ of GDP
1990	0.6092340354003399
1991	0.6205447304195599
1992	0.6348191925194085
1993	0.6432952235408438
1994	0.6378534130184107
1995	0.6543186372279847
1996	0.6651408723757081
1997	0.6604753920231559
1998	0.6502492193113111
1999	0.6208986171037438
2000	0.6167099875026436
2001	0.6444685600454074
2002	0.6085558010399712
2003	0.618854945411688
2004	0.6134088920200925
2005	0.58180157741099
2006	0.5478763899128047
2007	0.530020492479548
2008	0.5366792743537669
2009	0.5023527632195811
2010	0.507293909288559
2011	0.48489790284449863
2012	0.48746803417192447
2013	0.4883753648207535
2014	0.4860405424739649
2015	0.4618246074296275
2016	0.46266356398426595
2017	0.45713050898941104
2018	0.45492658890657556
2019	0.45648575779536765
2020	0.4249588134542024