Year	Percent
1961-01-01	70.600400000000000
1962-01-01	72.136200000000000
1963-01-01	71.244200000000000
1964-01-01	79.928000000000000
1965-01-01	84.344100000000000
1966-01-01	90.751400000000000
1967-01-01	73.540900000000000
1968-01-01	58.029900000000000
1969-01-01	56.843300000000000
1970-01-01	50.544200000000000
1971-01-01	38.101700000000000
1972-01-01	32.551800000000000
1973-01-01	26.068900000000000
1974-01-01	20.442800000000000
1975-01-01	18.649000000000000
1976-01-01	13.901900000000000
1977-01-01	11.234600000000000
1978-01-01	13.175100000000000
1979-01-01	12.489300000000000
1980-01-01	9.928230000000001
1981-01-01	8.964970000000000
1982-01-01	9.380530000000000
1983-01-01	9.604130000000000
1984-01-01	8.216460000000001
1985-01-01	8.043439999999999
1986-01-01	9.088590000000000
1987-01-01	11.584900000000000
1988-01-01	14.072900000000000
1989-01-01	68.074100000000000
1990-01-01	112.330000000000000
1991-01-01	103.804000000000000
1992-01-01	81.614300000000000
1993-01-01	63.359900000000000
1994-01-01	59.825600000000000
1995-01-01	47.787500000000000
1996-01-01	30.140700000000000
1997-01-01	23.356600000000000
1998-01-01	29.740700000000000
1999-01-01	34.877900000000000
2000-01-01	34.614100000000000
2001-01-01	31.818000000000000
2002-01-01	32.796700000000000
2003-01-01	37.945200000000000
2004-01-01	45.025600000000000
2005-01-01	47.216700000000000
2006-01-01	49.633999999999990
2007-01-01	56.495000000000000
2008-01-01	62.322800000000000
2009-01-01	61.652200000000000
2010-01-01	57.700700000000000
2011-01-01	59.135400000000000
2012-01-01	63.507800000000000
2013-01-01	66.906700000000000
2014-01-01	70.153500000000000
2015-01-01	73.633800000000000
2016-01-01	77.917800000000000
