Year	kg per kg of oil equivalent energy use
1990	2.5488754721056837
1991	2.4861516615670625
1992	2.706411035068345
1993	2.537350166042556
1994	2.47057928657908
1995	2.4416596361525436
1996	2.482174160508467
1997	2.4998661978763494
1998	2.442113760828048
1999	2.4118444555188656
2000	2.476542571834016
2001	2.5122378432982244
2002	2.5228236205572134
2003	2.517881008946273
2004	2.5425260838359147
2005	2.5219972027525652
2006	2.5322438455603167
2007	2.5114001703909046
2008	2.5107548415501704
2009	2.533821716823646
2010	2.528528600012431
2011	2.569349127665249
2012	2.596182695138372
2013	2.5865496214166
2014	2.5978558735431503