Year	% of total
1960	0
1961	0
1962	0
1963	0.4547630445189086
1964	3.146747749046539
1965	4.24970336828341
1966	4.321415786647575
1967	3.275826231552692
1968	2.495857999631822
1969	1.5317665948983687
1970	2.726273863480291
1971	2.7154615881213684
1972	2.708112387410937
1973	2.1832179882709357
1974	2.3141550280277428
1975	2.6067033434400253
1976	2.3531520617122936
1977	2.0520374883303627
1978	2.5577781757057285
1979	1.4681646266180257
1980	1.2034402694659734
1981	1.5126792360047834
1982	3.74203909231903
1983	3.2108334397503735
1984	3.8338640361620167
1985	3.8543215702628997
1986	4.6364382328807014
1987	0.08774937970266072
1988	0
1989	0
1990	0
1991	0
1992	0
1993	0
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