Year	Percent
1991-01-01	14.73799991607670
1992-01-01	15.51200008392330
1993-01-01	19.54199981689450
1994-01-01	15.28600025177000
1995-01-01	15.36200046539310
1996-01-01	15.62800025939940
1997-01-01	16.42600059509280
1998-01-01	14.47500038146970
1999-01-01	13.80799961090090
2000-01-01	14.52999973297120
2001-01-01	14.67199993133540
2002-01-01	12.19799995422360
2003-01-01	13.20300006866460
2004-01-01	12.82800006866460
2005-01-01	15.27999973297120
2006-01-01	13.87199974060060
2007-01-01	11.42300033569340
2008-01-01	10.83399963378910
2009-01-01	13.88799953460690
2010-01-01	10.18799972534180
2011-01-01	8.59500026702881
2012-01-01	8.49600028991699
2013-01-01	8.57400035858154
2014-01-01	9.71000003814697
2015-01-01	8.71399974822998
2016-01-01	9.60700035095215
2017-01-01	9.82699966430664