Year	kg per kg of oil equivalent energy use
1971	0.268131105521492
1972	0.25317069078989823
1973	0.26531371071145005
1974	0.2857159251311123
1975	0.28234116544971577
1976	0.3712649446234571
1977	0.37809899915269357
1978	0.3870910548075209
1979	0.37238722055627227
1980	0.3608957402170939
1981	0.4419906804000046
1982	0.45899132334918613
1983	0.48369907498257925
1984	0.4889681567683267
1985	0.5007954963323208
1986	0.5760694280423775
1987	0.6047992719223119
1988	0.6549840846293115
1989	0.6518758939446381
1990	0.6536483833096652
1991	0.641688719368989
1992	0.5561374400993632
1993	0.4476221352982666
1994	0.13227052803787115
1995	0.531538544222235
1996	0.5453813913811217
1997	0.6201265741815428
1998	0.6391827828554587
1999	0.6644911803241272
2000	0.731234507901561
2001	0.778984933944512
2002	0.7924911678375038
2003	0.8160666848215203
2004	0.7299770997004471
2005	0.5020366245993249
2006	0.49042683957824434
2007	0.5551349712717653
2008	0.5453954385597262
2009	0.527018294685325
2010	0.6479527721447738
2011	0.7124868667041401
2012	0.6139104746633007
2013	0.666161067497489
2014	0.7368385820239799