Year	Percent
1973-01-01	5.5567600000000000
1974-01-01	7.3423399999999990
1975-01-01	6.6406600000000005
1976-01-01	4.8297700000000000
1977-01-01	4.1978599999999995
1978-01-01	4.6651000000000000
1979-01-01	6.2747800000000010
1980-01-01	6.2478300000000000
1981-01-01	8.1795600000000000
1982-01-01	8.5725000000000000
1983-01-01	7.2238100000000000
1984-01-01	6.1496100000000000
1985-01-01	5.7622000000000000
1986-01-01	7.0101700000000000
1987-01-01	7.7076500000000000
1988-01-01	8.9161100000000000
1989-01-01	10.2437000000000000
1990-01-01	11.3733000000000000
1991-01-01	12.7950000000000000
1992-01-01	12.9968000000000000
1993-01-01	14.3619000000000000
1994-01-01	16.6087000000000000
1995-01-01	16.4964000000000000
1996-01-01	16.1222000000000000
1997-01-01	14.5707000000000000
1998-01-01	15.1036000000000000
1999-01-01	14.7089000000000000
2000-01-01	15.6008000000000000
2001-01-01	16.5610000000000000
2002-01-01	18.5929000000000000
2003-01-01	20.5591000000000000
2004-01-01	17.9605000000000000
2005-01-01	16.5258000000000000
2006-01-01	16.1433000000000000
2007-01-01	16.3036000000000000
2008-01-01	16.1365000000000000
2009-01-01	16.6105000000000000
2010-01-01	19.2445000000000000
2011-01-01	22.3747000000000000
2012-01-01	22.3267000000000000
2013-01-01	20.7086000000000000
2014-01-01	20.9584000000000000
2015-01-01	22.3495000000000000
2016-01-01	22.3046000000000000