Year	% of total electricity output
1990	14.36525822345953
1991	15.352872002934756
1992	14.105564320483543
1993	13.48306980064675
1994	13.232345888817651
1995	13.293881211366319
1996	12.73839323749791
1997	12.516602886778438
1998	14.875592353529905
1999	15.435671729396525
2000	15.983737519340051
2001	17.584168096932064
2002	18.035637392962737
2003	16.93033504797303
2004	16.944776785352406
2005	17.691273155603213
2006	18.472923938468668
2007	18.173468960632352
2008	18.288642494705808
2009	19.75533847304231
2010	21.162999328090535
2011	21.323779349693595
2012	21.795825040308046
2013	22.732603939598196
2014	24.966589430213567
2015	25.67587875450767