Year	% of total
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	17.532467532467532
1981	40.08620689655172
1982	19.248826291079812
1983	23.021582733812952
1984	20.35175879396985
1985	19.636363636363637
1986	22.58064516129032
1987	24.404761904761905
1988	28.783382789317507
1989	20.97457627118644
1990	13.876651982378855
1991	16.772823779193207
1992	11.778846153846153
1993	4.081632653061225
1994	0
1995	0
1996	0
1997	0
1998	0
1999	0
2000	0
2001	0
2002	0
2003	0
2004	0
2005	0
2006	0
2007	0
2008	0
2009	0
2010	0
2011	0
2012	0
2013	0
2014	0
2015	0