Year Percent 1990-01-01 1.9062100000000000 1991-01-01 1.4955900000000000 1992-01-01 1.6405000000000000 1993-01-01 1.8179599999999998 1994-01-01 1.9208100000000000 1995-01-01 1.6191700000000000 1996-01-01 1.6444900000000002 1997-01-01 1.5704900000000000 1998-01-01 1.5738000000000000 1999-01-01 1.6066400000000000 2000-01-01 1.7907900000000000 2001-01-01 1.7247500000000000 2002-01-01 1.8051000000000000 2003-01-01 1.5868600000000000 2004-01-01 1.6582100000000000 2005-01-01 1.6026100000000000 2006-01-01 1.5339300000000000 2007-01-01 1.6548100000000000 2008-01-01 1.8642400000000001 2009-01-01 1.8000700000000000 2010-01-01 1.7111299999999998 2011-01-01 1.5995200000000000 2012-01-01 1.6408400000000000 2013-01-01 1.6135100000000000 2014-01-01 1.7562799999999998 2015-01-01 1.4325100000000000 2016-01-01 1.4847500000000000