Year	Percent
1991-01-01	1.6127200000000002
1992-01-01	1.7012200000000002
1993-01-01	1.9592700000000000
1994-01-01	2.0532000000000000
1995-01-01	2.0561900000000000
1996-01-01	2.1453000000000000
1997-01-01	2.0905099999999996
1998-01-01	2.0562400000000003
1999-01-01	1.7563099999999998
2000-01-01	1.7600300000000000
2001-01-01	1.7659000000000000
2002-01-01	2.4035700000000000
2003-01-01	2.4438100000000000
2004-01-01	2.4180800000000000
2005-01-01	2.3712500000000000
2006-01-01	2.2758900000000000
2007-01-01	2.0291400000000000
2008-01-01	1.9011700000000000
2009-01-01	1.8233500000000000
2010-01-01	1.6902099999999998
2011-01-01	1.7160200000000000
2012-01-01	1.7399400000000000
2013-01-01	1.6526500000000000
2014-01-01	1.6157000000000000
2015-01-01	1.6734799999999999
2016-01-01	1.5116600000000000