Year Percent 1993-01-01 7.0383300000000000 1994-01-01 6.0483300000000000 1995-01-01 5.8375000000000000 1996-01-01 5.7508300000000006 1997-01-01 5.4895800000000000 1998-01-01 4.7279200000000000 1999-01-01 4.2040800000000000 2000-01-01 3.7405000000000000 2001-01-01 4.3230800000000000 2002-01-01 4.7266699999999995 2003-01-01 4.6158300000000000 2004-01-01 4.7441699999999996 2005-01-01 4.6025000000000000 2006-01-01 4.4078000000000000 2007-01-01 4.4646900000000000 2008-01-01 4.6396800000000000 2009-01-01 4.7249400000000000 2010-01-01 4.8062500000000000 2011-01-01 4.6795800000000005 2012-01-01 4.3824200000000000 2013-01-01 4.1083400000000000 2014-01-01 3.9434099999999996 2015-01-01 3.7532000000000000 2016-01-01 3.5341300000000000