Year Percent 1993-01-01 42.527700000000000 1994-01-01 24.005000000000000 1995-01-01 8.508230000000001 1996-01-01 7.667460000000000 1997-01-01 8.297970000000000 1998-01-01 9.859940000000000 1999-01-01 11.516500000000000 2000-01-01 12.768600000000000 2001-01-01 18.965000000000000 2002-01-01 22.332700000000000 2003-01-01 22.284400000000000 2004-01-01 25.595800000000000 2005-01-01 27.839200000000000 2006-01-01 31.721200000000000 2007-01-01 36.224000000000004 2008-01-01 40.596400000000000 2009-01-01 43.500300000000000 2010-01-01 45.872000000000000 2011-01-01 48.591600000000000 2012-01-01 51.482300000000000 2013-01-01 50.384800000000000 2014-01-01 51.575300000000000 2015-01-01 52.819700000000000 2016-01-01 52.326800000000000