Year Percent 1990-01-01 38.4785 1991-01-01 40.8645 1992-01-01 40.7322 1993-01-01 41.1196 1994-01-01 42.5126 1995-01-01 41.9240 1996-01-01 41.8546 1997-01-01 49.8963 1998-01-01 59.7970 1999-01-01 60.4350 2000-01-01 47.3077 2001-01-01 52.3664 2002-01-01 65.2322 2003-01-01 68.8956 2004-01-01 71.0344 2005-01-01 67.3207 2006-01-01 68.7398 2007-01-01 74.2743 2008-01-01 80.2158 2009-01-01 72.9855 2010-01-01 74.8404 2011-01-01 69.6156 2012-01-01 62.3022 2013-01-01 58.1987 2014-01-01 53.8906 2015-01-01 58.9073 2016-01-01 55.1908