Year Percent 1995-01-01 50 1996-01-01 20 1997-01-01 43 1998-01-01 43 1999-01-01 38 2000-01-01 38 2001-01-01 38 2002-01-01 38 2003-01-01 50 2004-01-01 63 2005-01-01 63 2006-01-01 63 2007-01-01 75 2008-01-01 75 2009-01-01 75 2010-01-01 83 2011-01-01 83 2012-01-01 83 2013-01-01 83