Year	Percent
1980-01-01	10.0000000000000000
1981-01-01	14.0833000000000000
1982-01-01	14.6667000000000000
1983-01-01	17.0000000000000000
1984-01-01	12.3333000000000000
1985-01-01	12.3333000000000000
1986-01-01	32.3900000000000000
1987-01-01	19.0642000000000000
1988-01-01	12.0567000000000000
1989-01-01	13.6067000000000000
1990-01-01	17.9792000000000000
1991-01-01	17.3725000000000000
1992-01-01	22.2883000000000000
1993-01-01	31.6958000000000000
1994-01-01	37.1417000000000000
1995-01-01	32.1475000000000000
1996-01-01	36.8083000000000000
1997-01-01	35.3217000000000000
1998-01-01	26.5925000000000000
1999-01-01	23.1100000000000000
2000-01-01	23.6133000000000000
2001-01-01	10.2383000000000000
2002-01-01	11.0525000000000000
2003-01-01	6.2533900000000004
2004-01-01	7.0501200000000000
2005-01-01	11.6810000000000000
2006-01-01	7.8647700000000000
2007-01-01	9.3152700000000000
2008-01-01	9.2175000000000000
2009-01-01	8.9203400000000000
2010-01-01	8.8632600000000000
2011-01-01	9.5123600000000010
2012-01-01	9.5087900000000000
2013-01-01	9.3122200000000000
2014-01-01	6.7440899999999990
2015-01-01	6.6593600000000000
2016-01-01	6.5082400000000000