Year	kg per 2011 PPP $ of GDP
1990	0.79262849574294
1991	0.782416256928508
1992	0.749465879827445
1993	0.729421390051209
1994	0.701722321043166
1995	0.697914791929368
1996	0.674524723440202
1997	0.640736207004777
1998	0.598930991659026
1999	0.569780790050807
2000	0.549812416680667
2001	0.534126178255305
2002	0.542326770624596
2003	0.580082612839604
2004	0.607951998480733
2005	0.617615449053604
2006	0.610840839699112
2007	0.587344703944807
2008	0.583025000048578
2009	0.574159217532428
2010	0.570601696391689
2011	0.587917030352484
2012	0.564045182001782
2013	0.53270927915401
2014	0.501658710462731