Year	Percent
1960-01-01	60.398200000000000
1961-01-01	63.030300000000000
1962-01-01	73.024100000000000
1963-01-01	94.932700000000000
1964-01-01	107.868000000000000
1965-01-01	104.767999999999990
1966-01-01	97.345400000000000
1967-01-01	90.184800000000000
1968-01-01	77.498000000000000
1969-01-01	65.997800000000000
1970-01-01	71.945200000000000
1971-01-01	76.570200000000000
1972-01-01	71.403800000000000
1973-01-01	70.023900000000000
1974-01-01	69.087900000000000
1975-01-01	71.494300000000000
1976-01-01	67.346100000000000
1977-01-01	58.393500000000000
1978-01-01	55.003000000000000
1979-01-01	50.973700000000000
1980-01-01	47.864000000000000
1981-01-01	50.660800000000000
1982-01-01	43.556400000000000
1983-01-01	37.196300000000000
1984-01-01	29.835800000000000
1985-01-01	19.889000000000000
1986-01-01	24.748600000000000
1987-01-01	26.943200000000000
1988-01-01	28.851800000000000
1989-01-01	38.300400000000000
1990-01-01	36.756300000000000
1991-01-01	44.347200000000000
1992-01-01	46.718000000000000
1993-01-01	48.131600000000000
1994-01-01	52.043200000000000
1995-01-01	50.065000000000000
1996-01-01	45.429900000000000
1997-01-01	41.182800000000000
1998-01-01	37.007900000000000
1999-01-01	27.900000000000000
2000-01-01	22.525400000000000
2001-01-01	20.935600000000000
2002-01-01	21.915400000000000
2003-01-01	30.089300000000000
2004-01-01	38.243200000000000
2005-01-01	32.614000000000004
2006-01-01	32.298600000000000
2007-01-01	33.778200000000000
2008-01-01	39.273000000000000
2009-01-01	45.671900000000000
2010-01-01	47.916000000000004
2011-01-01	47.336100000000000
2012-01-01	43.213100000000000
2013-01-01	36.893400000000000
2014-01-01	32.006400000000000
2015-01-01	29.189200000000000
2016-01-01	27.730700000000000