Year	Percent
1965	31.64227
1966	42.78679
1967	29.38043
1968	34.24406
1969	31.90039
1970	32.12238
1971	23.40287
1972	22.9934
1973	16.09667
1974	16.79505
1975	19.20931
1976	26.49642
1977	18.55316
1978	12.32734
1979	16.39811
1980	18.90449
1981	11.03116
1982	12.93075
1983	7.1529
1984	9.64636
1985	7.1709
1986	7.15653
1987	6.30174
1988	10.7794
1989	24.04247
1990	20.25938
1991	26.152
1992	41.3906
1993	24.41622
1994	49.45835
1995	23.29875
1996	21.35291
1997	26.20858
1998	23.91922
1999	21.26052
2000	20.76139
2001	22.27615
2002	25.09189
2003	30.6469
2004	21.9797
2005	11.43502
2006	46.17243
2007	44.11228
2008	10.07861
2009	12.41814
2010	10.77402
2011	10.66731
2012	11.00139
2013	11.95312
2014	11.92654
2015	11.29846
2016	11.29042
2017	17.33535
2018	14.92157
2019	17.27325
2020	19.44013
2021	13.80497