Year	Percent
1987-01-01	3.92500000000000
1988-01-01	3.60000000000000
1989-01-01	3.00000000000000
1990-01-01	2.75000000000000
1991-01-01	2.62500000000000
1992-01-01	2.82500000000000
1993-01-01	3.42500000000000
1994-01-01	3.70000000000000
1995-01-01	6.22500000000000
1996-01-01	5.45000000000000
1997-01-01	3.73250000000000
1998-01-01	3.16000000000000
1999-01-01	2.50250000000000
2000-01-01	2.50666666666667
2001-01-01	2.75666666666667
2002-01-01	2.97833333333333
2003-01-01	3.40583333333333
2004-01-01	3.91583333333333
2005-01-01	3.55963876730030
2006-01-01	3.56378701941168
2007-01-01	3.64655706908326
2008-01-01	3.90370434899731
2009-01-01	5.37418394170396
2010-01-01	5.32862295912074
2011-01-01	5.19542801925573
2012-01-01	4.92257616288964
2013-01-01	4.94315647500475
2014-01-01	4.83121318795654
2015-01-01	4.33564823408792
2016-01-01	3.88532438426956
2017-01-01	3.43797769004083