Year	% of total electricity output
1990	98.050139275766
1991	98.0417754569191
1992	97.9823455233291
1993	84.3648208469055
1994	84.1552990556139
1995	84.2553191489362
1996	81.5602836879433
1997	82.5046040515654
1998	82.5065274151436
1999	82.5168918918919
2000	84.257748776509
2001	85.956493921945
2002	85.9680012248335
2003	87.334282076249
2004	85.9477789081044
2005	85.7892350540838
2006	85.7467922381645
2007	86.7887184562098
2008	89.8722414503044
2009	90.689456520621
2010	91.0552272143267
2011	90.8516584875241
2012	91.3475557000206
2013	91.0347150336056
2014	91.3059975696562
2015	91.3068289899182