Year	Percent
1995-01-01	5
1996-01-01	5
1997-01-01	5
1998-01-01	5
1999-01-01	9
2000-01-01	13
2001-01-01	12
2002-01-01	11
2003-01-01	11
2004-01-01	11
2005-01-01	10
2006-01-01	15
2007-01-01	15
2008-01-01	15
2009-01-01	15
2010-01-01	15
2011-01-01	20
2012-01-01	28
2013-01-01	28