Year	Percent
1965	14.69269
1966	11.23754
1967	4.18469
1968	3.32918
1969	1.41184
1970	14.55641
1971	12.52319
1972	13.37174
1973	66.54842
1974	78.95098
1975	83.28201
1976	84.47383
1977	76.38709
1978	63.68744
1979	27.11022
1980	23.21023
1981	18.2637
1982	18.19887
1983	15.26066
1984	17.13167
1985	15.26594
1986	13.72793
1987	16.37002
1988	12.92099
1989	13.05117
1990	48.80625
1991	60.9558
1992	45.83579
1993	26.88567
1994	25.14709
1995	16.73281
1996	17.88872
1997	14.58687
1998	10.82263
1999	8.26206
2000	7.02215
2001	7.36557
2002	8.53937
2003	7.5026
2004	11.26216
2005	6.4962
2006	4.51765
2007	4.18668
2008	4.63188
2009	2.70745
2010	1.40305
2011	1.04984
2012	4.05387
2013	13.44769
2014	8.48488
2015	5.36426
2016	4.8747
2017	0.07776
2018	4.23569
2019	2.67015
2020	2.5433
2021	12.78921