Year	Percent
1966-01-01	50.401100000000000
1967-01-01	49.583600000000000
1968-01-01	55.903800000000000
1969-01-01	59.872400000000000
1970-01-01	61.490600000000000
1971-01-01	65.111800000000000
1972-01-01	60.119200000000000
1973-01-01	66.693800000000000
1974-01-01	80.644400000000000
1975-01-01	78.258400000000000
1976-01-01	69.958300000000000
1977-01-01	74.618800000000000
1978-01-01	81.049100000000000
1979-01-01	86.360700000000000
1980-01-01	82.640900000000000
1981-01-01	69.519200000000000
1982-01-01	75.189500000000000
1983-01-01	81.628700000000000
1984-01-01	59.333999999999996
1985-01-01	63.276800000000000
1986-01-01	71.192700000000000
1987-01-01	70.503400000000000
1988-01-01	81.775700000000000
1989-01-01	81.148300000000000
1990-01-01	80.869500000000000
1991-01-01	105.539000000000000
1992-01-01	132.164000000000000
1993-01-01	70.453800000000000
1994-01-01	55.913900000000000
1995-01-01	59.640600000000000
1996-01-01	56.159200000000000
1997-01-01	62.612300000000000
1998-01-01	66.188000000000000
1999-01-01	64.543300000000000
2000-01-01	64.016400000000000
2001-01-01	58.452400000000000
2002-01-01	48.757100000000000
2003-01-01	53.876400000000000
2004-01-01	61.371100000000000
2005-01-01	68.230500000000000
2006-01-01	73.647400000000000
2007-01-01	78.251400000000000
2008-01-01	88.951200000000000
2009-01-01	91.478700000000000
2010-01-01	82.864700000000000
2011-01-01	79.469100000000000
2012-01-01	73.345100000000000
2013-01-01	66.147100000000000
2014-01-01	67.539300000000000
2015-01-01	75.892100000000000
2016-01-01	86.014300000000000