Year	kg per kg of oil equivalent energy use
1971	1.4034114896667336
1972	1.3088429091383127
1973	1.3146231924840408
1974	1.3075934793301505
1975	1.3688975888245498
1976	1.3746764064903891
1977	1.4138313817922052
1978	1.417680679665888
1979	1.4275072584681945
1980	1.4763306368635438
1981	1.5152572556366868
1982	1.5110142110078284
1983	1.5781083850351274
1984	1.5610432171220887
1985	1.6328614522343778
1986	1.6841591332130939
1987	1.726414776921946
1988	1.7695580214174687
1989	1.8412577717762835
1990	1.7172298194117905
1991	1.768188249591426
1992	1.779242454525395
1993	1.8018352134564752
1994	1.829440117796886
1995	1.870702646360562
1996	1.8990347506133831
1997	1.9333971593594619
1998	1.9274759520937372
1999	1.9686133901627931
2000	1.990790950988092
2001	1.9933335450001495
2002	2.0077171912348275
2003	2.0118166287679404
2004	2.0525859548624212
2005	2.0668192941553367
2006	2.1001243284771656
2007	2.1889258983786273
2008	2.222940593841282
2009	2.234568328679438
2010	2.2615751731710123
2011	2.296723863733534
2012	2.3711457723761638
2013	2.384104356809007
2014	2.446459862897122