Year	kg per PPP $ of GDP
1990	0.7990733417962959
1991	0.7767159646344773
1992	0.720935302888217
1993	0.6748099102534216
1994	0.6242548825280461
1995	0.6014847161226543
1996	0.5634394403579894
1997	0.5501068952328261
1998	0.5241370898074494
1999	0.5132426545081545
2000	0.4954981931357292
2001	0.47637352780242126
2002	0.462480845842328
2003	0.4429230345004814
2004	0.4225766381054028
2005	0.3985786879878759
2006	0.37908642172205104
2007	0.3677821172487952
2008	0.3591239995444621
2009	0.3495722734542711
2010	0.33935654451255315
2011	0.33176319011692584
2012	0.31850908077545487
2013	0.3095850778686857
2014	0.31019122023003554
2015	0.2966207033893528
2016	0.28815553085035367
2017	0.2811279751294206
2018	0.27024608091693036
2019	0.25169649536087524
2020	0.23493814196313964