Year	% of energy use
1990	34.38924098793946
1991	31.573246451424975
1992	18.126435611227883
1993	15.603401735509962
1994	47.17071457539813
1995	45.330641124142346
1996	36.43784895074122
1997	20.357282167401458
1998	23.07271489919795
1999	21.111303904365155
2000	29.226363998223736
2001	26.31178207510918
2002	24.872425387149377
2003	20.815961049409083
2004	25.40465503524734
2005	27.692547009639128
2006	26.310701135556403
2007	30.600710471134896
2008	28.99464869635989
2009	28.854920088074415
2010	32.562020092490314
2011	35.372746570174
2012	32.446098736585
2013	28.459619795711312
2014	22.73008923303759