Year	Percent
1997-01-01	5.5405900000000000
1998-01-01	1.6447400000000000
1999-01-01	4.9413100000000000
2000-01-01	7.8525300000000010
2001-01-01	8.6869800000000000
2002-01-01	6.0663400000000000
2003-01-01	5.6817100000000000
2004-01-01	4.5230900000000000
2005-01-01	5.9891800000000000
2006-01-01	4.7820400000000000
2007-01-01	5.5192500000000000
2008-01-01	5.0142700000000000
2009-01-01	3.8096800000000000
2010-01-01	4.2605000000000000
2011-01-01	4.7609100000000000
2012-01-01	4.1727300000000005
2013-01-01	4.3044199999999995
2014-01-01	4.1517100000000000
2015-01-01	4.8151000000000000
2016-01-01	4.0580099999999995