Year	Percent
1960-01-01	12.380200000000000
1961-01-01	13.245700000000000
1962-01-01	15.227700000000000
1963-01-01	15.164500000000000
1964-01-01	15.288000000000000
1965-01-01	14.480900000000000
1966-01-01	15.140100000000000
1967-01-01	16.445200000000000
1968-01-01	17.426200000000000
1969-01-01	17.594200000000000
1970-01-01	15.109600000000000
1971-01-01	14.577900000000000
1972-01-01	14.412900000000000
1973-01-01	14.067600000000000
1974-01-01	12.577900000000000
1975-01-01	11.728200000000000
1976-01-01	13.028600000000000
1977-01-01	14.649900000000000
1978-01-01	16.022700000000000
1979-01-01	15.687400000000000
1980-01-01	16.296600000000000
1981-01-01	16.980800000000000
1982-01-01	18.093000000000000
1983-01-01	19.784900000000000
1984-01-01	20.379500000000000
1985-01-01	20.557000000000000
1986-01-01	19.705900000000000
1987-01-01	18.464700000000000
1988-01-01	19.332400000000000
1989-01-01	21.020800000000000
1990-01-01	22.265300000000000
1991-01-01	24.212800000000000
1992-01-01	25.612600000000000
1993-01-01	28.549200000000000
1994-01-01	32.585300000000000
1995-01-01	36.003300000000000
1996-01-01	39.537300000000000
1997-01-01	44.362700000000000
1998-01-01	48.139800000000000
1999-01-01	48.360300000000000
2000-01-01	48.273800000000000
2001-01-01	48.066300000000000
2002-01-01	47.685800000000000
2003-01-01	46.842300000000000
2004-01-01	44.621300000000000
2005-01-01	43.690700000000000
2006-01-01	44.752100000000000
2007-01-01	44.483999999999995
2008-01-01	47.058900000000000
2009-01-01	52.502100000000000
2010-01-01	51.057400000000000
2011-01-01	51.409000000000000
2012-01-01	49.990400000000000
2013-01-01	54.402400000000000
2014-01-01	60.457600000000000
2015-01-01	62.793800000000000
2016-01-01	64.148400000000000