Year	Percent
1980-01-01	9.4209000000000000
1981-01-01	11.1205000000000000
1982-01-01	15.1870000000000010
1983-01-01	14.8076000000000000
1984-01-01	10.7035000000000000
1985-01-01	6.3555199999999990
1986-01-01	6.1465100000000000
1987-01-01	9.1290600000000000
1988-01-01	6.5737500000000000
1989-01-01	8.3569000000000000
1990-01-01	7.4233100000000010
1991-01-01	6.4958500000000000
1992-01-01	6.7494399999999990
1993-01-01	7.1443300000000000
1994-01-01	4.9999300000000000
1995-01-01	5.0107400000000000
1996-01-01	4.0473000000000000
1997-01-01	4.1782600000000000
1998-01-01	4.7090800000000000
1999-01-01	4.5975199999999990
2000-01-01	7.4090100000000000
2001-01-01	4.5277900000000000
2002-01-01	3.4994400000000003
2003-01-01	3.2387900000000003
2004-01-01	2.4886200000000000
2005-01-01	2.2918600000000000
2006-01-01	2.5465200000000000
2007-01-01	3.6201800000000004
2008-01-01	9.1355399999999990
2009-01-01	2.8136600000000000
2010-01-01	2.7646200000000000
2011-01-01	4.2690300000000000
2012-01-01	3.6004500000000000
2013-01-01	4.3339700000000000
2014-01-01	2.8855500000000000
2015-01-01	1.8818500000000000
2016-01-01	1.6255800000000000