Year	kg per 2011 PPP $ of GDP
1990	0.315808698818303
1991	0.325520308567401
1992	0.322112337729084
1993	0.327247302466356
1994	0.327954129744387
1995	0.321876676407069
1996	0.320332210147501
1997	0.315252953116858
1998	0.317515374057047
1999	0.32543831952505
2000	0.32337347425998
2001	0.322165748698094
2002	0.320919128226052
2003	0.320060245619034
2004	0.315594289368325
2005	0.307491309079273
2006	0.305442471522768
2007	0.299396066287391
2008	0.308916891307402
2009	0.315057306080202
2010	0.299362085559057
2011	0.301231564470916
2012	0.305574068115178
2013	0.285602154129256
2014	0.287543446106062