Year	kg per 2011 PPP $ of GDP
1990	0.325873458264764
1991	0.335104456509178
1992	0.32380008061666
1993	0.341782008364084
1994	0.344419180523718
1995	0.357600040760506
1996	0.346811897337018
1997	0.348836270715711
1998	0.331857827595381
1999	0.327112747493433
2000	0.340618433365903
2001	0.330993944436236
2002	0.309781800777906
2003	0.325181938026745
2004	0.336364068541218
2005	0.303844540619824
2006	0.300264662509505
2007	0.291657624453953
2008	0.289337424002884
2009	0.275471121149983
2010	0.261173548304842
2011	0.253397773225241
2012	0.246609896752916
2013	0.239248611195579
2014	0.23919788302554