Year	kg per 2010 US$ of GDP
1968	0.300626803616485
1969	0.333680739849499
1970	0.352082145596312
1971	0.39431326014514
1972	0.425973529286666
1973	0.453077233641689
1974	0.463805161443283
1975	0.420703015424198
1976	0.45248548527275
1977	0.406571582592189
1978	0.40677040803169
1979	0.479821061835293
1980	0.444559464411005
1981	0.417017388387045
1982	0.416640334908124
1983	0.445648335774347
1984	0.473622885507223
1985	0.475087121695924
1986	0.464666771702206
1987	0.440008602144009
1988	0.499411476399566
1989	0.444860846886552
1990	0.312839129688146
1991	0.342187511599886
1992	0.380286885391917
1993	0.393296482597691
1994	0.385969555456216
1995	0.409999254825122
1996	0.392603490105106
1997	0.36385035326362
1998	0.334178486367472
1999	0.328004057388112
2000	0.387570401296001
2001	0.417122362350821
2002	0.418932598489138
2003	0.438282271378295
2004	0.449161508509318
2005	0.425852881847737
2006	0.378044837003677
2007	0.318451508872076
2008	0.339310107547387
2009	0.324339252185285
2010	0.339875449515599
2011	0.361566665227228
2012	0.365925971707227
2013	0.363915959481146
2014	0.358075749198181