Year	Percent
1976-01-01	0.1854410000000000
1977-01-01	0.8172610000000000
1978-01-01	0.8691270000000001
1979-01-01	1.0994800000000000
1980-01-01	1.8671600000000000
1981-01-01	1.8817700000000002
1982-01-01	2.8418500000000000
1983-01-01	3.6481700000000000
1984-01-01	2.6465400000000003
1985-01-01	2.2554200000000000
1986-01-01	2.6466500000000000
1987-01-01	3.0776500000000000
1988-01-01	2.8730300000000000
1989-01-01	2.6335500000000000
1990-01-01	2.4648900000000000
1991-01-01	2.4852300000000000
1992-01-01	2.8754100000000000
1993-01-01	3.0373300000000000
1994-01-01	3.4081300000000003
1995-01-01	3.1673000000000000
1996-01-01	2.8955800000000000
1997-01-01	3.1641000000000000
1998-01-01	3.2125700000000000
1999-01-01	3.5240400000000003
2000-01-01	3.6866000000000000
2001-01-01	3.8979500000000000
2002-01-01	5.2226700000000000
2003-01-01	5.3053900000000000
2004-01-01	5.5043700000000000
2005-01-01	6.6851800000000000
2006-01-01	7.5572100000000000
2007-01-01	8.2428800000000000
2008-01-01	9.7571600000000000
2009-01-01	10.2663000000000000
2010-01-01	9.4121300000000000
2011-01-01	9.3837600000000000
2012-01-01	10.5879000000000000
2013-01-01	9.2452200000000000
2014-01-01	8.6690500000000000
2015-01-01	7.8407000000000000
2016-01-01	6.1170100000000000
2017-01-01	5.4052600000000000