Year Percent 1961 10.86957 1962 10.86957 1963 10.86957 1964 10.86957 1965 10.86957 1966 10.86957 1967 10.86957 1968 10.86957 1969 10.86957 1970 10.86957 1971 10.86957 1972 10.86957 1973 10.86957 1974 10.86957 1975 10.86957 1976 10.86957 1977 10.86957 1978 10.86957 1979 10.86957 1980 10.86957 1981 10.86957 1982 13.04348 1983 13.04348 1984 13.04348 1985 13.04348 1986 13.04348 1987 13.04348 1988 10.86957 1989 10.86957 1990 8.69565 1991 8.69565 1992 8.69565 1993 8.69565 1994 8.69565 1995 8.69565 1996 8.69565 1997 8.69565 1998 8.69565 1999 8.69565 2000 8.69565 2001 8.69565 2002 8.69565 2003 8.69565 2004 8.69565 2005 8.69565 2006 8.69565 2007 6.52174 2008 6.52174 2009 6.30435 2010 5.21739 2011 3.26087 2012 3.26087 2013 3.36957 2014 3.36957 2015 3.36957 2016 3.36957 2017 3.36957 2018 3.36957 2019 3.36957 2020 3.36957 2021 3.36957