Year	kg per 2010 US$ of GDP
1981	0.515490368269405
1982	0.452133326827167
1983	0.424640936049021
1984	0.359335026850142
1985	0.389641490480843
1986	0.366823806433219
1987	0.345581699386176
1988	0.379609107287386
1989	0.397049577978139
1990	0.416797047624227
1991	0.386726531795865
1992	0.379837879717186
1993	0.373845671131448
1994	0.358080509553836
1995	0.350874696759778
1996	0.353831424521254
1997	0.357642343450299
1998	0.34629636818668
1999	0.337092870021582
2000	0.35367094020512
2001	0.398485666401768
2002	0.361014379324015
2003	0.385095136721509
2004	0.417800557264775
2005	0.367339063118016
2006	0.379418564903886
2007	0.375753713432736
2008	0.325505543331891
2009	0.325201733737172
2010	0.378327967187385
2011	0.34585058184212
2012	0.335554908841251
2013	0.342341166081297
2014	0.341469985789714