Year	Percent
1961	33.054
1962	35.42831
1963	37.59777
1964	44.27374
1965	42.34637
1966	41.99255
1967	43.02607
1968	44.01304
1969	44.18063
1970	46.75978
1971	47.23464
1972	51.96462
1973	54.47858
1974	52.43017
1975	54.09683
1976	55.83799
1977	56.21974
1978	55.38175
1979	54.58101
1980	55.27933
1981	55.28864
1982	56.63873
1983	57.53259
1984	57.18808
1985	57.93296
1986	60.06518
1987	62.6257
1988	63.20298
1989	63.054
1990	62.76536
1991	62.89572
1992	63.08194
1993	62.66294
1994	62.25326
1995	62.23464
1996	61.59218
1997	62.26257
1998	62.14153
1999	62.01117
2000	61.02421
2001	61.97393
2002	62.54347
2003	62.38722
2004	61.34762
2005	62.35438
2006	62.29447
2007	62.19466
2008	61.69673
2009	61.19692
2010	60.70274
2011	59.96276
2012	60.06245
2013	60.85492
2014	60.36224
2015	59.94524
2016	59.8491
2017	60.69364
2018	60.69364
2019	61.66667
2020	61.66667
2021	61.66667