Year	% of total energy
1990	5.9285618199529235
1991	6.057249004742386
1992	4.872482286473086
1993	5.700104883747472
1994	6.075085166366398
1995	5.332938120417451
1996	4.437495456192264
1997	4.209802117481745
1998	4.220147880521866
1999	5.782208238080717
2000	5.844952801435014
2001	5.361514749798585
2002	5.04919988322945
2003	4.823310938267574
2004	4.434513185271944
2005	4.993300719589219
2006	4.703958393492298
2007	4.831032687445457
2008	4.776796430603064
2009	6.9603632126660315
2010	6.57370583242326
2011	6.316704499736068
2012	7.046580517814395
2013	6.936531605551301
2014	7.768874503640941