Year	Percent
1995-01-01	4
1996-01-01	4
1997-01-01	4
1998-01-01	4
1999-01-01	4
2000-01-01	4
2001-01-01	6
2002-01-01	6
2003-01-01	9
2004-01-01	9
2005-01-01	9
2006-01-01	7
2007-01-01	5
2008-01-01	5
2009-01-01	5
2010-01-01	5
2011-01-01	8
2012-01-01	8
2013-01-01	8