Year	kg per 2010 US$ of GDP
1991	0.344454112415587
1992	0.324144270551397
1993	0.322015513493814
1994	0.309963931695966
1995	0.304160016026484
1996	0.310596854376335
1997	0.295586353677105
1998	0.28752493919808
1999	0.2710778043538
2000	0.265685743554601
2001	0.268711711941816
2002	0.261176573642377
2003	0.260852564743849
2004	0.255952603984602
2005	0.24805082082775
2006	0.244988777016181
2007	0.226813684128637
2008	0.224390400105176
2009	0.219991331524521
2010	0.222077547778405
2011	0.206794122980508
2012	0.207850284367755
2013	0.211716359486341
2014	0.19696260966307