Year	Percent
1960-01-01	10.229500000000000
1961-01-01	11.028100000000000
1962-01-01	11.223800000000000
1963-01-01	11.645500000000000
1964-01-01	11.662600000000000
1965-01-01	10.700999999999999
1966-01-01	10.178800000000000
1967-01-01	11.011200000000000
1968-01-01	12.915300000000000
1969-01-01	12.575500000000000
1970-01-01	12.452500000000000
1971-01-01	11.685800000000000
1972-01-01	11.420500000000000
1973-01-01	11.098200000000000
1974-01-01	10.985400000000000
1975-01-01	13.041400000000000
1976-01-01	15.476100000000000
1977-01-01	20.205500000000000
1978-01-01	23.328800000000000
1979-01-01	23.379300000000000
1980-01-01	23.993300000000000
1981-01-01	26.530900000000000
1982-01-01	27.626300000000000
1983-01-01	29.201900000000000
1984-01-01	28.812800000000000
1985-01-01	26.292600000000000
1986-01-01	25.131000000000000
1987-01-01	51.298600000000000
1988-01-01	82.083600000000000
1989-01-01	89.053400000000000
1990-01-01	72.245500000000000
1991-01-01	65.052500000000000
1992-01-01	76.796100000000000
1993-01-01	58.865500000000000
1994-01-01	22.398400000000000
1995-01-01	16.652400000000000
1996-01-01	15.254300000000000
1997-01-01	14.390000000000000
1998-01-01	13.121700000000000
1999-01-01	13.936900000000000
2000-01-01	15.779600000000000
2001-01-01	17.747600000000000
2002-01-01	19.381700000000000
2003-01-01	20.915200000000000
2004-01-01	19.552800000000000
2005-01-01	17.121900000000000
2006-01-01	15.272700000000000
2007-01-01	14.823800000000000
2008-01-01	17.191200000000000
2009-01-01	18.786800000000000
2010-01-01	22.010000000000000
2011-01-01	20.711500000000000
2012-01-01	19.360500000000000
2013-01-01	16.621500000000000
2014-01-01	14.179300000000000
2015-01-01	14.234200000000000
2016-01-01	13.452500000000000