Year	Percent
1980-01-01	5.2937000000000000
1981-01-01	4.5282599999999995
1982-01-01	5.8926099999999995
1983-01-01	6.7210300000000010
1984-01-01	6.9690900000000000
1985-01-01	6.1370200000000000
1986-01-01	6.1459100000000000
1987-01-01	3.3699400000000000
1988-01-01	3.2786400000000000
1989-01-01	3.0788200000000000
1990-01-01	2.7966300000000000
1991-01-01	2.5433600000000000
1992-01-01	2.3552400000000002
1993-01-01	1.3626300000000000
1994-01-01	0.9062750000000000
1995-01-01	0.7432330000000000
1996-01-01	0.8031330000000000
1997-01-01	0.6859980000000000
1998-01-01	0.7444700000000000
1999-01-01	1.1787800000000000
2000-01-01	1.3078900000000000
2001-01-01	1.0866799999999999
2002-01-01	3.4844100000000000
2003-01-01	4.2214800000000010
2004-01-01	3.9023300000000000
2005-01-01	3.0368800000000000
2006-01-01	3.2706800000000000
2007-01-01	3.1722799999999998
2008-01-01	3.5345100000000000
2009-01-01	3.6688300000000003
2010-01-01	3.9745699999999995
2011-01-01	4.9158000000000000
2012-01-01	5.1347900000000000
2013-01-01	4.7263100000000000
2014-01-01	4.7170700000000000
2015-01-01	4.8373300000000010
2016-01-01	4.7028000000000000