Year	% of total electricity output
1990	22.990501503008748
1991	23.41764828371477
1992	23.693932220332513
1993	24.779912299254814
1994	25.55006537908061
1995	25.69144861504121
1996	24.879505345634886
1997	24.74476144927334
1998	25.111567005013733
1999	24.308864667738458
2000	23.69176873861739
2001	23.37688973784919
2002	22.684085379947266
2003	21.41404503257327
2004	22.157470121750144
2005	22.289814888611208
2006	21.8800693884581
2007	21.19227150475036
2008	21.58258442226136
2009	21.910132940202384
2010	22.095928635488754
2011	21.265896991268235
2012	22.234845289791057
2013	22.62524879708448
2014	23.30549902727031
2015	23.680957898598734