Year	Percent
1961-01-01	7.2636199999999995
1962-01-01	19.0320000000000000
1963-01-01	15.3611000000000000
1964-01-01	11.2109999999999990
1965-01-01	10.5184000000000000
1966-01-01	11.2043000000000000
1967-01-01	12.5733000000000000
1968-01-01	12.3668000000000000
1969-01-01	13.8467000000000000
1970-01-01	11.8525000000000000
1971-01-01	16.5844000000000000
1972-01-01	19.1901000000000000
1973-01-01	14.6603000000000000
1974-01-01	8.4468800000000000
1975-01-01	9.1049300000000000
1976-01-01	10.7611000000000000
1977-01-01	13.3979000000000000
1978-01-01	14.8476000000000000
1979-01-01	17.0023000000000000
1980-01-01	21.6938000000000000
1981-01-01	25.8383000000000000
1982-01-01	31.3400000000000000
1983-01-01	31.0381000000000000
1984-01-01	30.6831000000000000
1985-01-01	32.7771000000000000
1986-01-01	34.3050000000000000
1987-01-01	32.9282000000000000
1988-01-01	32.0548000000000000
1989-01-01	33.2740000000000000
1990-01-01	33.9095000000000000
1991-01-01	32.0263000000000000
1992-01-01	32.0097000000000000
1993-01-01	33.7029000000000000
1994-01-01	33.3544000000000000
1995-01-01	32.2741000000000000
1996-01-01	35.7641000000000000
1997-01-01	39.4801000000000000
1998-01-01	44.2459000000000000
1999-01-01	49.1409000000000000
2000-01-01	49.8208000000000000
2001-01-01	42.7732000000000000
2002-01-01	34.4246000000000000
2003-01-01	33.0615000000000000
2004-01-01	30.6763000000000000
2005-01-01	29.8800000000000000
2006-01-01	29.2277000000000000
2007-01-01	30.1132000000000000
2008-01-01	36.2739000000000000
2009-01-01	39.7247000000000000
2010-01-01	36.4430000000000050
2011-01-01	38.4108000000000000
2012-01-01	42.5041000000000000
2013-01-01	45.8106000000000000
2014-01-01	48.1710000000000100
2015-01-01	50.8746000000000000
2016-01-01	53.0238000000000000