Year	Percent
1962-01-01	11.205300000000000
1963-01-01	11.617700000000000
1964-01-01	13.325300000000000
1965-01-01	12.037000000000000
1966-01-01	12.309800000000000
1967-01-01	6.462240000000000
1968-01-01	10.116700000000000
1969-01-01	11.378600000000000
1970-01-01	4.398470000000000
1971-01-01	4.470310000000000
1972-01-01	6.219080000000000
1973-01-01	7.760520000000000
1974-01-01	8.520170000000000
1975-01-01	10.297000000000000
1976-01-01	12.860100000000000
1977-01-01	13.955000000000000
1978-01-01	12.386600000000000
1979-01-01	12.150500000000000
1980-01-01	12.304200000000000
1981-01-01	12.357999999999999
1982-01-01	12.879500000000000
1983-01-01	13.581600000000000
1984-01-01	14.945200000000000
1985-01-01	14.596100000000000
1986-01-01	16.017500000000000
1987-01-01	17.935000000000000
1988-01-01	18.924200000000000
1989-01-01	18.874100000000000
1990-01-01	18.810900000000000
1991-01-01	18.899700000000000
1992-01-01	19.487400000000000
1993-01-01	19.765600000000000
1994-01-01	21.229700000000000
1995-01-01	21.938300000000000
1996-01-01	22.400000000000000
1997-01-01	22.693900000000000
1998-01-01	22.088100000000000
1999-01-01	19.684800000000000
2000-01-01	20.089900000000000
2001-01-01	19.430999999999997
2002-01-01	18.235700000000000
2003-01-01	21.377700000000000
2004-01-01	23.542500000000000
2005-01-01	20.285400000000000
2006-01-01	19.629800000000000
2007-01-01	21.134100000000000
2008-01-01	22.254100000000000
2009-01-01	24.176500000000000
2010-01-01	25.792900000000000
2011-01-01	26.419400000000000
2012-01-01	27.209000000000000
2013-01-01	29.808800000000000
2014-01-01	31.875200000000000
2015-01-01	33.836200000000000
2016-01-01	35.145500000000000