Year	Percent
1995-01-01	17
1996-01-01	17
1997-01-01	17
1998-01-01	17
1999-01-01	17
2000-01-01	20
2001-01-01	23
2002-01-01	27
2003-01-01	27
2004-01-01	31
2005-01-01	30
2006-01-01	33
2007-01-01	33
2008-01-01	36
2009-01-01	37
2010-01-01	37
2011-01-01	36
2012-01-01	39
2013-01-01	36