Year	kg per kg of oil equivalent energy use
1971	1.0799401923095957
1972	1.1176137115313738
1973	1.2280911128365088
1974	1.3977270931822434
1975	1.1573512145704266
1976	1.2381121374306336
1977	1.1303286745527366
1978	1.0877929060163103
1979	1.3143459744241446
1980	1.3117729360443906
1981	1.2690842422408628
1982	1.2324962625276448
1983	1.1797008555793917
1984	1.2617080371247622
1985	1.2546390207897946
1986	1.2584920380832565
1987	1.1332713264988787
1988	1.2332804224895788
1989	1.0332471283589986
1990	1.5078815579356062
1991	1.5103356583052805
1992	1.5454724486329365
1993	1.5444835509356858
1994	1.5018690489993598
1995	1.4738277136094535
1996	1.4600338065209775
1997	1.4282458150080406
1998	1.4240659322428186
1999	1.4120868717532042
2000	1.4121434552752095
2001	1.4225047956749164
2002	1.4051995507592658
2003	1.3497275129892128
2004	1.3802064970240868
2005	1.3960689147486742
2006	1.4119732057468213
2007	1.4084708713515226
2008	1.3898629834899838
2009	1.3327732950521294
2010	1.3660520836850933
2011	1.3585704918696573
2012	1.2675360483651146
2013	1.3198404998810074
2014	1.1480844543816555