Year	% of total electricity output
1990	57.6493986761553
1991	57.1646100175919
1992	54.0463589717136
1993	59.400554499327
1994	58.9666410987759
1995	62.0502079536258
1996	64.9481081063624
1997	66.5546114348086
1998	65.0985103517873
1999	61.847810107951
2000	61.1259803089257
2001	59.6193643817127
2002	60.2930672045339
2003	59.7626389344839
2004	56.232061074084
2005	56.4033591820571
2006	54.3533046855736
2007	58.849799131578
2008	54.9408347243365
2009	58.1708546342934
2010	52.2846324063118
2011	48.0190533691882
2012	49.6895063677508
2013	50.7720298205657
2014	53.3069563549091
2015	54.5964565549528