Year	Percent
1980-01-01	3.1730500000000000
1981-01-01	2.7180600000000000
1982-01-01	3.9003600000000000
1983-01-01	3.9474400000000003
1984-01-01	5.3867800000000000
1985-01-01	6.5411300000000000
1986-01-01	4.8058800000000000
1987-01-01	8.1310800000000000
1988-01-01	10.2742000000000000
1989-01-01	8.7914600000000000
1990-01-01	6.9665500000000000
1991-01-01	7.0913800000000000
1992-01-01	7.2403400000000000
1993-01-01	6.6942800000000000
1994-01-01	7.3899000000000000
1995-01-01	6.4742300000000000
1996-01-01	5.3507099999999990
1997-01-01	5.1455000000000000
1998-01-01	5.6433300000000010
1999-01-01	5.2434500000000000
2000-01-01	2.8633800000000000
2001-01-01	3.1135900000000003
2002-01-01	3.3291199999999996
2003-01-01	2.9931600000000000
2004-01-01	2.6433200000000000
2005-01-01	1.9559400000000002
2006-01-01	1.7895100000000000
2007-01-01	2.0647000000000000
2008-01-01	1.3112900000000000
2009-01-01	1.5876800000000000
2010-01-01	3.0701600000000000
2011-01-01	3.4765200000000000
2012-01-01	3.9176699999999998
2013-01-01	4.4935100000000000
2014-01-01	5.4781100000000000
2015-01-01	5.6118000000000000
2016-01-01	8.8239200000000000