Year	Percent
1961	7.72639
1962	7.76919
1963	7.76919
1964	7.812
1965	7.8334
1966	7.87621
1967	7.87621
1968	7.91901
1969	7.91901
1970	8.17584
1971	8.17584
1972	8.24005
1973	8.24005
1974	8.38987
1975	8.38987
1976	8.51829
1977	8.56109
1978	8.56109
1979	8.66811
1980	8.83933
1981	8.83933
1982	8.94634
1983	9.20318
1984	9.50281
1985	9.50281
1986	9.50281
1987	9.95227
1988	9.84526
1989	9.67404
1990	9.71684
1991	10.78698
1992	10.78698
1993	10.80838
1994	12.78894
1995	14.19598
1996	14.32161
1997	14.37186
1998	14.37186
1999	14.37186
2000	14.52261
2001	14.54774
2002	14.57286
2003	14.64824
2004	15.32125
2005	15.55736
2006	15.1376
2007	14.77031
2008	13.67631
2009	13.64221
2010	13.64221
2011	13.63171
2012	13.63171
2013	13.63171
2014	13.78912
2015	13.78912
2016	13.60633
2017	13.44904
2018	13.45045
2019	13.45045
2020	13.45045
2021	13.45045