Year	Percent
1987-01-01	3.5000000000000000
1988-01-01	3.5000000000000000
1989-01-01	3.5000000000000000
1990-01-01	3.2500000000000000
1991-01-01	3.7500000000000000
1992-01-01	3.7500000000000000
1993-01-01	3.7500000000000000
1994-01-01	3.8206000000000000
1995-01-01	4.2454000000000000
1996-01-01	4.1387000000000000
1997-01-01	2.3501000000000000
1998-01-01	5.1688000000000000
1999-01-01	3.7874000000000000
2000-01-01	5.2979999999999990
2001-01-01	5.5544000000000000
2002-01-01	5.5419199999999990
2003-01-01	5.6771199999999995
2004-01-01	5.9321000000000000
2005-01-01	5.7622599999999995
2006-01-01	5.8759700000000000
2007-01-01	4.7800000000000000
2008-01-01	4.9488199999999996
2009-01-01	5.2334000000000000
2010-01-01	5.2221000000000000
2011-01-01	5.1904699999999995
2012-01-01	5.1983300000000000
2013-01-01	5.1962199999999990
2014-01-01	5.1954000000000000
2015-01-01	5.2243000000000000
2016-01-01	5.2059700000000000