Year Percent 1995-01-01 33 1996-01-01 33 1997-01-01 83 1998-01-01 86 1999-01-01 100 2000-01-01 100 2001-01-01 91 2002-01-01 91 2003-01-01 90 2004-01-01 90 2005-01-01 90 2006-01-01 90 2007-01-01 90 2008-01-01 83 2009-01-01 83 2010-01-01 85 2011-01-01 85 2012-01-01 85 2013-01-01 85