Year	kg per 2010 US$ of GDP
1970	0.585937406641102
1971	0.56874326012623
1972	0.683653865853708
1973	0.63063823927424
1974	0.528831442743376
1975	0.396557729253009
1976	0.387301406245481
1977	0.363494861061801
1978	0.380751197497056
1979	0.333789013612787
1980	0.352203597866575
1981	0.381236443971475
1982	0.427674364347093
1983	0.326939089888167
1984	0.442962930785323
1985	0.379565866129524
1986	0.452523129682569
1987	0.543052332240086
1988	0.543472027616095
1989	0.541730355700177
1990	0.507082554532246
1991	0.454538591480016
1992	0.42720655756072
1993	0.535551020496619
1994	0.462735103637948
1995	0.381733467235235
1996	0.388168568933603
1997	0.414653167689308
1998	0.33587341026905
1999	0.350889362485739
2000	0.289100332925291
2001	0.346047605265099
2002	0.310748414843722
2003	0.340255196131488
2004	0.337790755513843
2005	0.341239669089326
2006	0.319630738742887
2007	0.325329535821604
2008	0.295729245860496
2009	0.284082179895508
2010	0.292821021289492
2011	0.286887570502634
2012	0.29471175020532
2013	0.246047092015254
2014	0.227414339148824