Year	kg per kg of oil equivalent energy use
1971	6.127549182846502
1972	6.516246426648292
1973	6.2789078890127215
1974	5.8647692701989715
1975	5.232128409015773
1976	5.168410138651019
1977	4.832563812602398
1978	4.944488346054927
1979	4.406082369715502
1980	3.1767097738361443
1981	2.6342734339876714
1982	2.7526502583639894
1983	3.497588679078745
1984	3.0243435871968507
1985	2.98890348164244
1986	2.7407585767607885
1987	2.889178829028252
1988	3.1193570463733056
1989	2.8860214168904887
1990	2.585355011043724
1991	2.832184488083792
1992	2.884943591874669
1993	2.6551524341977846
1994	2.7008147488848255
1995	2.691401502772287
1996	2.8705384594023724
1997	2.6671850017307275
1998	2.631763566308444
1999	2.5860177921446663
2000	2.769822491729225
2001	2.629813682484323
2002	2.6708351938949426
2003	2.7383900756055843
2004	2.697607979309859
2005	2.6131083091869365
2006	2.719513810754732
2007	2.7429676821697884
2008	2.6101622218093365
2009	2.700081985188922
2010	2.696705327471121
2011	2.6965515606912014
2012	2.6349367234561845
2013	2.681332728808538
2014	2.5758494920010335