Year	Percent
1960-01-01	2.6183400000000003
1961-01-01	3.9817400000000003
1962-01-01	5.7472800000000000
1963-01-01	4.3518500000000000
1964-01-01	3.0599500000000000
1965-01-01	3.4181400000000000
1966-01-01	3.6997900000000000
1967-01-01	4.1201900000000000
1968-01-01	5.0765699999999990
1969-01-01	5.9380500000000000
1970-01-01	3.0666800000000000
1971-01-01	2.8818099999999998
1972-01-01	3.2980400000000003
1973-01-01	2.7401200000000000
1974-01-01	3.8046200000000000
1975-01-01	5.1314100000000000
1976-01-01	5.0688300000000000
1977-01-01	4.2517000000000000
1978-01-01	5.0258600000000000
1979-01-01	5.1602600000000000
1980-01-01	5.0337000000000000
1981-01-01	4.9999300000000000
1982-01-01	5.2049199999999995
1983-01-01	5.8768000000000000
1984-01-01	8.1072700000000000
1985-01-01	9.9262000000000000
1986-01-01	9.3860400000000000
1987-01-01	9.2976300000000000
1988-01-01	10.4627000000000000
1989-01-01	10.1591000000000000
1990-01-01	9.1941600000000000
1991-01-01	9.6904000000000000
1992-01-01	10.5588000000000000
1993-01-01	10.7397000000000000
1994-01-01	9.6857200000000000
1995-01-01	9.0872000000000000
1996-01-01	10.2445000000000000
1997-01-01	11.1964000000000000
1998-01-01	11.5357000000000000
1999-01-01	11.0344000000000000
2000-01-01	11.8151000000000000
2001-01-01	11.2518000000000000
2002-01-01	12.7951000000000000
2003-01-01	15.1643000000000000
2004-01-01	16.1236000000000000
2005-01-01	15.4147000000000000
2006-01-01	14.8322000000000000
2007-01-01	15.6691000000000000
2008-01-01	15.9529000000000000
2009-01-01	16.0102000000000000
2010-01-01	17.2328000000000000
2011-01-01	16.6656000000000000
2012-01-01	18.1064000000000000
2013-01-01	19.0702000000000000
2014-01-01	19.9095000000000000
2015-01-01	21.6981000000000000
2016-01-01	21.7808000000000000