{"Year":1972,"Percent":49.2}
{"Year":1973,"Percent":46.6}
{"Year":1974,"Percent":47.6}
{"Year":1975,"Percent":50.7}
{"Year":1976,"Percent":48.8}
{"Year":1977,"Percent":50.6}
{"Year":1978,"Percent":50.1}
{"Year":1979,"Percent":49.3}
{"Year":1980,"Percent":49.3}
{"Year":1981,"Percent":53.9}
{"Year":1982,"Percent":50.6}
{"Year":1983,"Percent":52.7}
{"Year":1984,"Percent":55.2}
{"Year":1985,"Percent":57.7}
{"Year":1986,"Percent":53.8}
{"Year":1987,"Percent":56.8}
{"Year":1988,"Percent":58.9}
{"Year":1989,"Percent":59.6}
{"Year":1990,"Percent":60.1}
{"Year":1991,"Percent":62.5}
{"Year":1992,"Percent":61.9}
{"Year":1993,"Percent":62.6}
{"Year":1994,"Percent":61.9}
{"Year":1995,"Percent":61.9}
{"Year":1996,"Percent":65}
{"Year":1997,"Percent":67}
{"Year":1998,"Percent":65.6}
{"Year":1999,"Percent":62.9}
{"Year":2000,"Percent":63.3}
{"Year":2001,"Percent":61.8}
{"Year":2002,"Percent":65.2}
{"Year":2003,"Percent":63.9}
{"Year":2004,"Percent":66.7}
{"Year":2005,"Percent":68.6}
{"Year":2006,"Percent":66}
{"Year":2007,"Percent":67.2}
{"Year":2008,"Percent":68.6}
{"Year":2009,"Percent":70.1}
{"Year":2010,"Percent":68.1}
{"Year":2011,"Percent":68.2}
{"Year":2012,"Percent":66.2}