Year	% of total
1960	0
1961	0
1962	0
1963	0
1964	0
1965	0
1966	0
1967	0
1968	0
1969	2.632911392405063
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	1.6257995735607675
1977	0.4751187796949237
1978	0.43363045049385696
1979	0.3089933322491462
1980	0.44068394147717255
1981	0.34416299559471364
1982	0.3893381251871818
1983	0.5245901639344263
1984	0.7535460992907801
1985	1.0017313875834777
1986	2.3859649122807016
1987	2.034618888551473
1988	4.704714640198511
1989	8.243157224697645
1990	10.602925262089956
1991	11.397278106508876
1992	12.052050955414014
1993	12.183595578673602
1994	12.74478042659975
1995	15.205696052241022
1996	14.823406682966587
1997	22.78179273216689
1998	27.339980024968792
1999	28.538744908350306
2000	28.64582848469517
2001	25.118506053268764
2002	30.059095022624433
2003	30.069746925260173
2004	29.496862130707253
2005	20.366359712230217
2006	19.87772055073942
2007	18.523898905344495
2008	17.49924914142991
2009	23.28135902636917
2010	29.937953098827467
2011	26.951663090128758
2012	26.033387692976735
2013	32.22587946282346
2014	33.594975988178795
2015	30.642826420890934
2016	26.30372637944067