Year	% of total
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	0
1991	0
1992	0
1993	0
1994	0
1995	0.2579166069637484
1996	16.018564095351945
1997	39.22266367248229
1998	33.84155075277716
1999	42.921554003661264
2000	39.06673901247965
2001	38.135175135668476
2002	35.75799965028851
2003	21.769128953223127
2004	30.442744802326832
2005	29.31003094847988
2006	30.78178004505788
2007	26.483877592934896
2008	31.531294414907617
2009	28.89600330476092
2010	37.5048844660953
2011	28.464764242610208
2012	27.329832149109258
2013	24.531385668318094
2014	22.979778997218673
2015	33.789113857480935