Year	kg per kg of oil equivalent energy use
1960	3.676417063630303
1961	3.7097027076639035
1962	3.609230365808083
1963	3.5206280254468907
1964	3.506838197088481
1965	3.440897622203635
1966	3.4229538263806303
1967	3.22341417378861
1968	3.2275460553800164
1969	3.1887146989633646
1970	3.183866758519542
1971	3.166927418857039
1972	3.084970635364559
1973	3.0266904813852604
1974	2.940845659247477
1975	3.027808045191967
1976	2.9457047516656885
1977	2.9122464363315643
1978	2.9295292099512666
1979	2.9710967739367384
1980	2.9193479552104633
1981	2.9148451214174775
1982	2.8672684791627163
1983	2.8679902648527698
1984	2.783454526515709
1985	2.7881561835035273
1986	2.7889921171944243
1987	2.781854579416179
1988	2.750679394160827
1989	2.8105608031958886
1990	2.7033954061615466
1991	2.6785484497256262
1992	2.606331814913395
1993	2.5220238607850667
1994	2.478828228510099
1995	2.4233325664461876
1996	2.4134444123347047
1997	2.381661412311128
1998	2.370369142363577
1999	2.3523499287231577
2000	2.377725994654494
2001	2.433281006112716
2002	2.4230020972679585
2003	2.435422771341288
2004	2.4470270554730593
2005	2.427910635498917
2006	2.4735111700670953
2007	2.507274880620032
2008	2.475577809634876
2009	2.374329043515491
2010	2.3759946922589523
2011	2.3637492579975032
2012	2.4097302003992884
2013	2.364662170356837
2014	2.3121638960308877
2015	2.224094005832507