Year	kg per kg of oil equivalent energy use
1990	2.399554366671183
1991	2.372539813137944
1992	2.3534320724370965
1993	2.319589509496357
1994	2.3223068497578168
1995	2.2884069880022415
1996	2.264584491956246
1997	2.243123389636984
1998	2.2406910338909665
1999	2.2294403674313816
2000	2.2160403533580153
2001	2.1971222483597477
2002	2.1997078582963616
2003	2.200110334483134
2004	2.179142234469542
2005	2.1670580869553824
2006	2.148702372716632
2007	2.1550803880430007
2008	2.113918689855666
2009	2.070591444960027
2010	2.051609432470412
2011	2.0594535703597687
2012	2.053928696832118
2013	2.030731966656307
2014	1.9973229108602355
2015	2.0111762247765927