Year	% of total electricity output
1990	55.663149342121415
1991	60.318735047695526
1992	59.152299502687555
1993	57.43399120099294
1994	54.75954778463656
1995	55.33754541543143
1996	54.61918238587266
1997	54.37480115514675
1998	48.37227325665355
1999	50.183373615824095
2000	52.85887291691802
2001	51.32355861074539
2002	46.263089703925594
2003	45.45188425129651
2004	45.64842788984026
2005	44.09333504880185
2006	40.84321020377386
2007	36.936289215622914
2008	41.72717141844774
2009	41.55021212324931
2010	38.54708440982412
2011	37.70364998882523
2012	36.03793509905538
2013	35.16386365018729
2014	34.56614593136318
2015	31.233531412489434