Year	kg per PPP $ of GDP
1997	0.47255595060792654
1998	0.4688947823996546
1999	0.35186927954050534
2000	0.41882013961548814
2001	0.4053215775693125
2002	0.40015030115528116
2003	0.42030715338577856
2004	0.42436786520746644
2005	0.39258279305208643
2006	0.3388055971657384
2007	0.2734062033388713
2008	0.3159605160456355
2009	0.21705012092416648
2010	0.3060140433432882
2011	0.2825972056370063
2012	0.2710058164673276
2013	0.2454591659235553
2014	0.23211700041752983
2015	0.23217474088264262
2016	0.18990621887725617
2017	0.18508289560995045
2018	0.18679468960759085
2019	0.17322603483141896
2020	0.19365850016583458