Year	Percent
1990-01-01	2.0068799999999998
1991-01-01	2.1138800000000000
1992-01-01	2.1007100000000000
1993-01-01	2.0773800000000000
1994-01-01	1.9417500000000000
1995-01-01	1.8534900000000000
1996-01-01	1.8093299999999999
1997-01-01	1.7383200000000000
1998-01-01	1.7987200000000000
1999-01-01	1.7242600000000000
2000-01-01	1.6688100000000000
2001-01-01	1.6917600000000000
2002-01-01	1.7060200000000000
2003-01-01	1.7170299999999998
2004-01-01	1.7425800000000000
2005-01-01	1.8178900000000002
2006-01-01	1.7674800000000000
2007-01-01	1.6088799999999999
2008-01-01	1.6063600000000000
2009-01-01	1.7613800000000000
2010-01-01	1.7321500000000000
2011-01-01	1.6536099999999998
2012-01-01	1.7235700000000000
2013-01-01	1.9224900000000003
2014-01-01	1.9204100000000000
2015-01-01	1.8321100000000000
2016-01-01	1.7775299999999998