Year Percent 1994-01-01 38.2748000000000000 1995-01-01 34.6357000000000000 1996-01-01 27.4930000000000020 1997-01-01 43.7519000000000000 1998-01-01 39.3416000000000000 1999-01-01 36.8631000000000000 2000-01-01 37.5128000000000000 2001-01-01 37.3108000000000000 2002-01-01 25.4229000000000000 2003-01-01 19.7197000000000000 2004-01-01 14.0888000000000000 2005-01-01 6.0049700000000000 2006-01-01 5.6882100000000000 2007-01-01 3.7970500000000000 2008-01-01 3.1179099999999997 2009-01-01 3.2795199999999998 2010-01-01 3.1323000000000000 2011-01-01 2.7414300000000000 2012-01-01 5.2061199999999990 2013-01-01 3.3218000000000000 2014-01-01 6.1678400000000000 2015-01-01 12.3232000000000000 2016-01-01 15.3229000000000000