Year	Percent
1996-01-01	38.61
1997-01-01	39.30
1998-01-01	39.46
1999-01-01	40.87
2000-01-01	37.47
2001-01-01	36.04
2002-01-01	35.82
2003-01-01	37.45
2004-01-01	31.18
2005-01-01	32.89
2006-01-01	33.31
2007-01-01	34.85
2008-01-01	29.20
2009-01-01	31.00
2010-01-01	29.05
2011-01-01	31.53
2012-01-01	26.55
2013-01-01	26.71
2014-01-01	28.17
2015-01-01	28.70