Year	% of total electricity output
1990	97.6608187134503
1991	97.6331360946746
1992	97.7272727272727
1993	97.4842767295598
1994	97.5308641975309
1995	97.5609756097561
1996	97.4025974025974
1997	97.2222222222222
1998	96.9230769230769
1999	96.969696969697
2000	96.4601769911504
2001	97.7978989934508
2002	98
2003	98.3277591973244
2004	58.6638830897704
2005	55.7724957555178
2006	22.4956063268893
2007	25.7042679240721
2008	37.2236503856041
2009	39.975845410628
2010	39.9501956599075
2011	43.2995658465991
2012	46.2609093916185
2013	35.8812993174227
2014	44.0581475957398
2015	56.8878281622912
