Year	kg per PPP $ of GDP
1990	1.1188973879015545
1991	0.9447726303828528
1992	0.9375352540864466
1993	0.9390081712822689
1994	0.8674213729272504
1995	0.8437841004124041
1996	0.965869996654329
1997	1.1089230930235368
1998	0.9896099356238535
1999	0.929457166314122
2000	0.827456683793092
2001	0.8284070051196659
2002	0.7008803892580501
2003	0.7323855996401671
2004	0.6656423221039365
2005	0.6087914707112293
2006	0.5645654659893511
2007	0.5436730200168985
2008	0.46551593226810944
2009	0.4064556409429645
2010	0.40451486547815796
2011	0.42898008555292366
2012	0.3774601541235461
2013	0.32790088644248633
2014	0.33048526356879543
2015	0.33763724378538307
2016	0.2907772615107203
2017	0.28905885669834397
2018	0.2530732176202764
2019	0.21991883895455241
2020	0.19130678904019943