Year	Percent
1980-01-01	0.7120000000000001
1981-01-01	0.7200000000000000
1982-01-01	0.7480000000000000
1983-01-01	0.7180000000000000
1984-01-01	0.7920000000000000
1985-01-01	0.8280000000000000
1986-01-01	1.0740000000000000
1987-01-01	1.0740000000000000
1988-01-01	0.8140000000000001
1989-01-01	0.9650000000000000
1990-01-01	1.0060000000000000
1991-01-01	1.0920000000000000
1992-01-01	1.2180000000000000
1993-01-01	1.3590000000000000
1994-01-01	1.3820000000000000
1995-01-01	1.4780000000000002
1996-01-01	1.3860000000000000
1997-01-01	1.4150000000000000
1998-01-01	1.5830000000000002
1999-01-01	2.3400000000000000
2000-01-01	2.3600000000000000
2001-01-01	2.6600000000000000
2002-01-01	3.0400000000000000
2003-01-01	3.3600000000000000
2004-01-01	3.4600000000000000
2005-01-01	3.6200000000000000
2006-01-01	3.5900000000000000
2007-01-01	3.9300000000000000
2008-01-01	4.3600000000000000
2009-01-01	4.9100000000000000
2010-01-01	4.9400000000000000
2011-01-01	5.2300000000000000
2012-01-01	5.3500000000000000
2013-01-01	5.7500000000000000
2014-01-01	6.0100000000000000
2015-01-01	6.3800000000000000
2016-01-01	6.8200000000000000