Year	Percent
1990-01-01	1.5771700000000002
1991-01-01	1.6178400000000000
1992-01-01	1.6927900000000002
1993-01-01	1.6728100000000000
1994-01-01	1.8043000000000000
1995-01-01	1.9424000000000000
1996-01-01	2.0059099999999996
1997-01-01	2.1512100000000000
1998-01-01	2.1570000000000000
1999-01-01	2.1711800000000000
2000-01-01	2.2632000000000000
2001-01-01	2.4158800000000000
2002-01-01	2.5918700000000000
2003-01-01	2.5525400000000000
2004-01-01	2.5480200000000000
2005-01-01	2.9984200000000000
2006-01-01	3.2215500000000000
2007-01-01	2.5988000000000000
2008-01-01	3.2297200000000000
2009-01-01	3.3452200000000000
2010-01-01	3.9031599999999997
2011-01-01	4.0108200000000000
2012-01-01	4.0404700000000000
2013-01-01	4.1032100000000000
2014-01-01	4.2110400000000010
2015-01-01	2.3068500000000000