Year	Percent
1995-01-01	7
1996-01-01	7
1997-01-01	8
1998-01-01	9
1999-01-01	9
2000-01-01	9
2001-01-01	9
2002-01-01	11
2003-01-01	12
2004-01-01	14
2005-01-01	15
2006-01-01	15
2007-01-01	17
2008-01-01	20
2009-01-01	20
2010-01-01	20
2011-01-01	19
2012-01-01	18
2013-01-01	17