Year	kg per PPP $ of GDP
1990	0.639096472549529
1991	0.6132174612880487
1992	0.6064396801255317
1993	0.5217093313552497
1994	0.4549448371673398
1995	0.3842755391405726
1996	0.3488947605635483
1997	0.3603315675457566
1998	0.32236057244069183
1999	0.30043305491658684
2000	0.2804652139709118
2001	0.2599261142830514
2002	0.2665740976268018
2003	0.2709680754754752
2004	0.26767141231986424
2005	0.2618057647252371
2006	0.26274778924772046
2007	0.2718805628160116
2008	0.2687369468955966
2009	0.275383585603238
2010	0.28308666946045363
2011	0.28676774206557526
2012	0.2749121492033668
2013	0.2574604967082713
2014	0.25477049650040007
2015	0.25391588808217935
2016	0.25275249469847844
2017	0.2240208849169869
2018	0.21237764634762124
2019	0.2038579242603449
2020	0.1874948725478793