Year kg per kg of oil equivalent energy use 1990 2.0057212233007036 1991 2.0116965871089265 1992 1.812991307713897 1993 1.7288685906096295 1994 1.8238024569488414 1995 1.576789294358101 1996 1.5137716519610256 1997 1.5634592614407141 1998 1.5738818216970578 1999 1.5382554074072585 2000 1.4739038383625336 2001 1.3471051375086263 2002 1.2658412073282053 2003 1.213704375982487 2004 1.2689715779134165 2005 1.4501714095824343 2006 1.4935267316622276 2007 1.3965864720142995 2008 1.3721868855497372 2009 1.3338795126832659 2010 1.7875710187069307 2011 1.6207479834075924 2012 1.6172306504385094 2013 1.6254860138621103 2014 1.5513472365091716