Year	kg per 2011 PPP $ of GDP
2006	0.610589060814632
2007	0.55717311693415
2008	0.523735794340855
2009	0.477312138377808
2010	0.471515344495826
2011	0.494923505234955
2012	0.446119079784565
2013	0.441659940983775
2014	0.376634580418616