Year	% of total electricity output
1990	99.2262573318358
1991	99.2815297888803
1992	99.0725254675384
1993	99.2925103683825
1994	99.3980343980344
1995	99.3311458859162
1996	99.288206559665
1997	99.3073920161189
1998	99.1582270156517
1999	99.3302421432251
2000	99.3844575532188
2001	99.3705149187964
2002	99.37446338771
2003	99.3741725839451
2004	99.4358251057828
2005	99.4068934646374
2006	99.8657302210287
2007	99.8755573991496
2008	99.8741346758968
2009	99.8787021126049
2010	99.8755742725881
2011	99.8695425291355
2012	99.8544631306598
2013	99.8571428571429
2014	97.1630224190423
2015	96.993823945234