Year	% of total energy use
1990	6.160907143763824
1991	5.403958397526339
1992	5.875673326018676
1993	5.6510754008591375
1994	5.902513807045504
1995	6.166509163955623
1996	4.681316375478629
1997	5.3342456846844035
1998	6.666564013832837
1999	6.474763693008702
2000	6.858272893703589
2001	6.352064620385277
2002	6.430585501653398
2003	6.112623487267959
2004	7.204493581772328
2005	7.619126700624874
2006	6.456278261833901
2007	7.060017943001469
2008	7.608457814606849
2009	7.664636003212431
2010	6.574202332014398
2011	6.451380679554357
2012	9.106979720377275
2013	7.417994175951524
2014	6.843845986003713