Year Percent 1995-01-01 29.1882 1996-01-01 27.8379 1997-01-01 41.2422 1998-01-01 38.5224 1999-01-01 26.5352 2000-01-01 27.4189 2001-01-01 33.6964 2002-01-01 39.8743 2003-01-01 48.5458 2004-01-01 47.7843 2005-01-01 39.7575 2006-01-01 49.8054 2007-01-01 47.9617 2008-01-01 29.9895 2009-01-01 32.7732 2010-01-01 33.8775 2011-01-01 28.2387 2012-01-01 33.9214 2013-01-01 23.3457 2014-01-01 21.0730 2015-01-01 16.8961 2016-01-01 13.0379