Year	kg per 2015 US$ of GDP
1990	0.590603818895661
1991	0.5807983800155987
1992	0.5590852996683484
1993	0.5342798315617567
1994	0.5002305796738845
1995	0.4860231490566092
1996	0.47946796196357966
1997	0.44959519643421
1998	0.4378923002822414
1999	0.42181946900095496
2000	0.40914124235911087
2001	0.4037156798310604
2002	0.39814783893462485
2003	0.40360128830007685
2004	0.39142144589999905
2005	0.38093621612552603
2006	0.3732847808832522
2007	0.36006870556880516
2008	0.3537884455013584
2009	0.3424216211724036
2010	0.34616829347079925
2011	0.3390118884329896
2012	0.3341951072708339
2013	0.3243790163146214
2014	0.30417480379957473
2015	0.2965585125507387
2016	0.2922525972054475
2017	0.28711649515828713
2018	0.2816351803379486
2019	0.27021140658680226
2020	0.26722818903947965