Year	kg per PPP $ of GDP
1990	0.8180366002208128
1991	0.7866253867677517
1992	0.753092094552629
1993	0.7209880788129363
1994	0.6808098505044138
1995	0.668861005596227
1996	0.6309086573902247
1997	0.5990330760600778
1998	0.5905494722239987
1999	0.5614398236966579
2000	0.5390997882009191
2001	0.5234802653815535
2002	0.5103891656282161
2003	0.5112461858037016
2004	0.498919660213204
2005	0.48308386157930083
2006	0.4581682047431464
2007	0.43578215740518744
2008	0.4124003526930833
2009	0.4061948447114843
2010	0.4009770273533027
2011	0.39385480137330053
2012	0.3780366440528446
2013	0.3666466756242478
2014	0.3555147480772181
2015	0.34440926474022343
2016	0.33048258648439716
2017	0.3188325824839582
2018	0.30690311993008174
2019	0.29098432806914426
2020	0.28086367133766216