Year	Percent
1980-01-01	9.1466500000000000
1981-01-01	8.0358200000000000
1982-01-01	6.4139000000000000
1983-01-01	6.1029500000000000
1984-01-01	5.3326800000000000
1985-01-01	4.6013900000000000
1986-01-01	4.4395000000000000
1987-01-01	4.8104600000000000
1988-01-01	3.6510800000000003
1989-01-01	3.3042500000000000
1990-01-01	2.4205000000000000
1991-01-01	2.3661200000000000
1992-01-01	2.0850299999999997
1993-01-01	1.5250299999999999
1994-01-01	0.1332460000000000
1995-01-01	0.1305440000000000
1996-01-01	32.2737000000000000
1997-01-01	42.6622000000000000
1998-01-01	36.3619000000000000
1999-01-01	38.7104000000000000
2000-01-01	41.0745000000000000
2001-01-01	44.3312000000000000
2002-01-01	41.1543000000000000
2003-01-01	40.5956000000000000
2004-01-01	41.7813000000000000
2005-01-01	46.8909000000000000
2006-01-01	44.3495000000000000
2007-01-01	41.1708000000000000
2008-01-01	34.5140000000000000
2009-01-01	36.9267000000000000
2010-01-01	32.9866000000000000
2011-01-01	29.9799000000000000
2012-01-01	28.5598000000000000
2013-01-01	27.9221000000000000
2014-01-01	29.3917000000000000
2015-01-01	28.6440000000000020
2016-01-01	31.3330000000000020