Year	% of total energy use
1990	5.491490015182459
1991	7.9823717365754945
1992	5.339826394162583
1993	4.959697701912053
1994	6.743860333634263
1995	6.686284817068685
1996	7.712973190068127
1997	6.369282819275894
1998	5.697693247748521
1999	6.536403210247667
2000	6.965848009840051
2001	6.68076671713292
2002	5.633475854451137
2003	4.821902509651506
2004	6.757096237003997
2005	6.898387547021885
2006	6.903705853757777
2007	5.024776160687878
2008	6.526079913848689
2009	7.940738896680251
2010	9.269955572495467
2011	7.073366579360557
2012	7.738147899307
2013	10.360052329076215
2014	11.943825812394088