Year Percent 1995-01-01 10 1996-01-01 10 1997-01-01 10 1998-01-01 10 1999-01-01 9 2000-01-01 9 2001-01-01 9 2002-01-01 9 2003-01-01 12 2004-01-01 12 2005-01-01 12 2006-01-01 14 2007-01-01 14 2008-01-01 14 2009-01-01 24 2010-01-01 24 2011-01-01 22 2012-01-01 23 2013-01-01 23