Year	kg per kg of oil equivalent energy use
1971	6.077246841736507
1972	6.583631057310127
1973	5.652800331161815
1974	5.485839047073495
1975	6.612273285325677
1976	7.735111472103389
1977	6.904627004767517
1978	6.362643059162903
1979	7.112540149242064
1980	6.125044062052621
1981	4.988899651294347
1982	5.6572988037672
1983	5.944618566423137
1984	4.978845049118145
1985	4.939061785252148
1986	4.871088509495354
1987	4.259976789396771
1988	4.255382979119616
1989	4.934195943036898
1990	2.578417913306857
1991	2.39494155278703
1992	2.170632196289905
1993	2.0552126809647215
1994	1.7764741045397967
1995	2.063136322740745
1996	2.026147056696078
1997	1.7884087029128968
1998	1.9030202067784987
1999	2.11832021556978
2000	2.2808899349008946
2001	1.9850907334865646
2002	1.9555385133312706
2003	1.494089316987741
2004	1.2900900699077733
2005	1.7109037285599769
2006	1.6041922199482619
2007	1.7840988751417344
2008	1.5584601018799684
2009	1.828501358779467
2010	1.668550359434704
2011	1.703771034788782
2012	1.6789593080827692
2013	1.6667866535474265
2014	1.5870151179788323