Year	kg per 2011 PPP $ of GDP
2007	1.1042875922249
2008	0.821524638925271
2009	0.693048355222782
2010	0.665827605676031
2011	0.546487517288075
2012	0.496416237621992
2013	0.403490710475003
2014	0.320174198147162