Year	Percent
1965	13.88541
1966	12.58642
1967	14.95061
1968	12.83627
1969	15.72758
1970	15.11909
1971	16.66568
1972	12.79863
1973	7.73573
1974	7.78766
1975	4.5301
1976	5.30139
1977	6.16523
1978	4.29064
1979	2.50213
1980	2.37768
1981	2.71758
1982	5.19693
1983	3.67699
1984	4.06432
1985	4.91289
1986	6.2001
1987	6.65772
1988	7.4675
1989	10.36033
1990	5.63438
1991	10.01173
1992	5.44564
1993	7.45363
1994	4.7008
1995	6.07901
1996	3.323
1997	3.5913
1998	3.25857
1999	4.41649
2000	5.22236
2001	4.51291
2002	5.0664
2003	4.12858
2004	1.78881
2005	2.83451
2006	2.34038
2007	3.16876
2008	2.53009
2009	3.82317
2010	1.72925
2011	0.96074
2012	1.47802
2013	1.54198
2014	0.68225
2015	0.7596
2016	1.23867
2017	1.77695
2018	1.79656
2019	1.54969
2020	4.28608
2021	1.82572