Year	% of total electricity output
1990	20.4079398906752
1991	18.4711307876776
1992	17.5846836703706
1993	18.1252601684878
1994	18.0884357039359
1995	19.2141393015674
1996	17.5522106198623
1997	17.5124660177764
1998	18.0611563169165
1999	16.6814659250101
2000	16.6394981921286
2001	18.9585191657511
2002	17.6186278990475
2003	15.0370403322247
2004	16.2232664186372
2005	16.1750249753446
2006	15.5927834152258
2007	15.263347136776
2008	17.7374440648538
2009	17.8637981987375
2010	18.6228260527723
2011	16.7617704327503
2012	19.9662489377563
2013	20.2962273802567
2014	22.6091537829535
2015	23.926817173663