Year	kg per kg of oil equivalent energy use
1990	2.7324243840675906
1991	2.5836155285244424
1992	2.6175577056024415
1993	2.566478590504679
1994	2.5075068966544007
1995	2.438965178932321
1996	2.307880100604395
1997	2.2875300135959074
1998	2.2792814320068846
1999	2.2636370471638436
2000	2.2226719353862436
2001	2.2413049040467206
2002	2.2414234432656377
2003	2.2831064276667283
2004	2.13514813370507
2005	2.0675598577510983
2006	2.213480901833531
2007	2.2399421366699968
2008	2.2380100392794415
2009	2.2027091725074097
2010	2.0347589629184095
2011	2.240260282339959
2012	2.2633726129301843
2013	2.3127210619291856
2014	2.2483241629822968