Year	kg per PPP $ of GDP
1990	0.8124099300637382
1991	0.7806748608221751
1992	0.748371377693174
1993	0.7283176393175301
1994	0.6952983271023472
1995	0.6697912326700786
1996	0.6532152369306446
1997	0.6462624068032464
1998	0.6168651866191274
1999	0.5823815938496374
2000	0.5634410540601498
2001	0.5432149280154875
2002	0.5117548842961384
2003	0.4939568539992755
2004	0.4696892805845138
2005	0.44124597549987166
2006	0.4091815017867867
2007	0.396312625447105
2008	0.3763324870604749
2009	0.356154236611835
2010	0.3583041923597301
2011	0.33164615904939904
2012	0.30491338423782005
2013	0.3016523205844219
2014	0.29004819248917746
2015	0.2727902988239586
2016	0.2602776838159276
2017	0.24573424613027073
2018	0.24085864237705915
2019	0.22385678995251004
2020	0.20262358163387337