Year	Percent
1960-01-01	10.4498000000000000
1961-01-01	11.2279000000000000
1962-01-01	13.4381000000000000
1963-01-01	14.9284000000000000
1964-01-01	15.9923000000000000
1965-01-01	15.9132000000000000
1966-01-01	16.1840000000000000
1967-01-01	16.7698000000000000
1968-01-01	16.3700000000000000
1969-01-01	16.9580000000000000
1970-01-01	9.6060500000000000
1971-01-01	9.7087899999999990
1972-01-01	8.9112900000000000
1973-01-01	8.0222199999999990
1974-01-01	6.9551700000000000
1975-01-01	6.5101600000000000
1976-01-01	7.7266400000000000
1977-01-01	10.1342000000000000
1978-01-01	11.0195000000000000
1979-01-01	10.7472000000000000
1980-01-01	15.6944000000000000
1981-01-01	19.9861000000000000
1982-01-01	20.0620000000000000
1983-01-01	18.7126000000000000
1984-01-01	14.3265000000000000
1985-01-01	13.9311000000000000
1986-01-01	15.6730000000000000
1987-01-01	14.9125000000000000
1988-01-01	15.6955000000000000
1989-01-01	13.8784000000000000
1990-01-01	10.0050000000000000
1991-01-01	9.6619800000000000
1992-01-01	8.7550500000000000
1993-01-01	5.6808100000000000
1994-01-01	4.1283400000000010
1995-01-01	4.2696700000000000
1996-01-01	4.2635100000000000
1997-01-01	3.0849100000000000
1998-01-01	2.3533500000000000
1999-01-01	3.0082600000000000
2000-01-01	4.7404600000000000
2001-01-01	5.6867700000000000
2002-01-01	4.6973199999999995
2003-01-01	3.5414100000000000
2004-01-01	3.6527300000000005
2005-01-01	3.7176900000000000
2006-01-01	3.0740900000000000
2007-01-01	2.7143300000000000
2008-01-01	3.3337199999999996
2009-01-01	3.0896200000000000
2010-01-01	1.6959099999999998
2011-01-01	2.4682800000000000
2012-01-01	3.0055000000000000
2013-01-01	1.9797700000000000
2014-01-01	1.8019999999999998
2015-01-01	2.3466600000000000
2016-01-01	2.8433599999999997