Year	kg per PPP $ of GDP
1990	1.9506146842418406
1991	1.829206897915451
1992	1.644618308572746
1993	1.5432448918280062
1994	1.3984920524697633
1995	1.377705296213028
1996	1.223589714580021
1997	1.123948362531379
1998	1.0641924034624661
1999	0.9497856890394337
2000	0.9084203264086549
2001	0.8647928827647932
2002	0.839342095884805
2003	0.8717999595775866
2004	0.8910253772388307
2005	0.8834699193049089
2006	0.8403182420606159
2007	0.7780551650175223
2008	0.7167122560836889
2009	0.6981014767407389
2010	0.6844585851850218
2011	0.6704932706295029
2012	0.6271334616851463
2013	0.6094197121593762
2014	0.5751541333179092
2015	0.5412292129113586
2016	0.511847398094412
2017	0.489897012468147
2018	0.47062122950198904
2019	0.4429010472512862
2020	0.4335101278475308