Year	kg per PPP $ of GDP
1990	1.165616139750697
1991	1.1328505436374738
1992	1.0918620243346258
1993	1.0261211598379556
1994	0.9463811178933914
1995	0.9208112494395554
1996	0.860399231062239
1997	0.799448148004207
1998	0.7782610741266038
1999	0.728316958984306
2000	0.691947036504969
2001	0.6665346535805847
2002	0.6439015739081425
2003	0.6480907136268214
2004	0.6401507279438047
2005	0.6253788052928845
2006	0.5876717516579436
2007	0.5511577899203012
2008	0.5127328270871515
2009	0.5034111252023752
2010	0.4992291007888468
2011	0.4889067428491067
2012	0.46443005993647823
2013	0.4514893587267382
2014	0.43265806134131596
2015	0.42262981018466456
2016	0.4060882812722557
2017	0.3894067676998473
2018	0.3725748485833008
2019	0.35288873780597435
2020	0.347310987566042