Year	% of total
1960	0
1961	0
1964	0
1965	0
1966	0
1967	0
1968	0
1969	0
1970	0
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	56.74199999999999
1991	58.51595744680851
1992	68.92192771084338
1993	79.36794520547946
1994	57.473173076923075
1995	61.238899999999994
1996	78.98153846153846
1997	57.4827027027027
1998	56.935
1999	53.502131147540986
2000	58.08787610619469
2001	59.41898148148148
2002	60.31700934579439
2003	64.90589999999999
2004	65.56151515151515
2005	64.26326732673266
2006	63.90019801980199
2007	65.23028846153845
2008	68.30686274509804
2009	64.08682242990655
2010	68.2570297029703
2011	68.66637254901961
2012	67.45896226415094
2013	46.84296774193549
2014	75.24989583333334
2015	72.98398058252428
2016	67.97365853658536