Year	Percent
1960-01-01	4.5851900000000000
1961-01-01	4.9321600000000000
1962-01-01	5.5471300000000000
1963-01-01	5.9183300000000000
1964-01-01	6.3167700000000000
1965-01-01	5.8841300000000000
1966-01-01	5.8972900000000000
1967-01-01	6.2996200000000000
1968-01-01	6.8550100000000010
1969-01-01	7.2800899999999995
1970-01-01	5.6239700000000000
1971-01-01	5.1964800000000000
1972-01-01	5.6625900000000000
1973-01-01	6.4074500000000000
1974-01-01	6.9236600000000010
1975-01-01	6.3881900000000000
1976-01-01	6.6358200000000000
1977-01-01	7.5447700000000000
1978-01-01	8.4767400000000000
1979-01-01	7.9322200000000000
1980-01-01	8.8076300000000000
1981-01-01	8.3236300000000000
1982-01-01	9.3115000000000000
1983-01-01	9.5702900000000000
1984-01-01	7.6639500000000000
1985-01-01	6.7722800000000000
1986-01-01	4.8055400000000010
1987-01-01	4.6422900000000000
1988-01-01	4.8550600000000000
1989-01-01	4.6792900000000000
1990-01-01	5.3850500000000000
1991-01-01	3.7226700000000000
1992-01-01	3.9443699999999997
1993-01-01	4.0958400000000000
1994-01-01	3.8667000000000000
1995-01-01	3.5230599999999996
1996-01-01	3.3036500000000000
1997-01-01	4.5073500000000000
1998-01-01	4.5264500000000000
1999-01-01	5.1990200000000000
2000-01-01	5.8621600000000000
2001-01-01	6.6161699999999990
2002-01-01	7.2431000000000000
2003-01-01	7.2491300000000000
2004-01-01	7.5091500000000000
2005-01-01	9.9029300000000000
2006-01-01	9.3986600000000010
2007-01-01	10.3020000000000000
2008-01-01	11.5388000000000000
2009-01-01	13.2963000000000000
2010-01-01	14.1271000000000000
2011-01-01	14.4626000000000000
2012-01-01	13.9626000000000000
2013-01-01	12.9641000000000000
2014-01-01	14.5573000000000000
2015-01-01	17.7992000000000000
2016-01-01	18.2676000000000000