Year	Percent
1960-01-01	11.1636000000000000
1961-01-01	11.7881000000000000
1962-01-01	13.3770000000000000
1963-01-01	13.6435000000000000
1964-01-01	13.3477000000000000
1965-01-01	13.6450000000000000
1966-01-01	14.9227000000000000
1967-01-01	16.9107000000000000
1968-01-01	16.5414000000000000
1969-01-01	18.6599000000000000
1970-01-01	21.6961000000000000
1971-01-01	17.1465000000000000
1972-01-01	13.8854000000000000
1973-01-01	13.2283000000000000
1974-01-01	14.2889000000000000
1975-01-01	14.3678000000000000
1976-01-01	10.9648000000000000
1977-01-01	9.6636400000000000
1978-01-01	10.4440000000000000
1979-01-01	8.9844800000000000
1980-01-01	13.9359000000000000
1981-01-01	11.0914000000000000
1982-01-01	11.6794000000000000
1983-01-01	12.5610000000000000
1984-01-01	10.9045000000000000
1985-01-01	8.8312300000000000
1986-01-01	8.9587100000000000
1987-01-01	8.5015500000000000
1988-01-01	7.4850600000000010
1989-01-01	7.2598800000000000
1990-01-01	7.3800399999999990
1991-01-01	6.9757899999999990
1992-01-01	5.7141100000000000
1993-01-01	4.4518900000000010
1994-01-01	3.8694100000000000
1995-01-01	3.8062000000000000
1996-01-01	4.5375100000000000
1997-01-01	4.1958100000000000
1998-01-01	4.2863800000000000
1999-01-01	4.4449100000000000
2000-01-01	4.8198800000000000
2001-01-01	5.0667500000000000
2002-01-01	5.5560199999999990
2003-01-01	6.3783000000000000
2004-01-01	6.7301899999999995
2005-01-01	6.9441100000000000
2006-01-01	6.6625399999999990
2007-01-01	6.5036900000000000
2008-01-01	6.6886600000000005
2009-01-01	6.5456699999999990
2010-01-01	7.5466700000000000
2011-01-01	8.9635900000000000
2012-01-01	10.6087000000000000
2013-01-01	15.9279999999999990
2014-01-01	13.9950000000000000
2015-01-01	12.8517000000000000