Year	Percent
1980-01-01	2.1810300000000000
1981-01-01	2.4278700000000000
1982-01-01	10.4898000000000000
1983-01-01	9.4321500000000000
1984-01-01	17.7096000000000000
1985-01-01	11.8669000000000000
1986-01-01	7.7522699999999990
1987-01-01	5.0400800000000010
1988-01-01	6.1413400000000005
1989-01-01	6.4552500000000000
1990-01-01	7.5811300000000000
1991-01-01	5.6139199999999990
1992-01-01	4.4521600000000000
1993-01-01	3.8693900000000000
1994-01-01	4.8995500000000000
1995-01-01	3.8145800000000003
1996-01-01	3.6331300000000004
1997-01-01	3.7519300000000000
1998-01-01	5.2271199999999990
1999-01-01	4.2065199999999990
2000-01-01	4.0185000000000000
2001-01-01	9.6216900000000000
2002-01-01	13.2985000000000000
2003-01-01	10.3179000000000000
2004-01-01	8.4918800000000000
2005-01-01	6.8993400000000000
2006-01-01	6.4825800000000005
2007-01-01	4.7801700000000000
2008-01-01	4.3346200000000000
2009-01-01	6.1465900000000000
2010-01-01	3.7606100000000000
2011-01-01	4.3517000000000000
2012-01-01	4.0608900000000006
2013-01-01	3.3228300000000000
2014-01-01	4.0438000000000000
2015-01-01	4.0164800000000005
2016-01-01	3.7617300000000005