Year	Percent
1960-01-01	11.430300000000000
1961-01-01	9.821520000000000
1962-01-01	8.916450000000000
1963-01-01	8.974520000000000
1964-01-01	9.585420000000000
1965-01-01	9.682390000000000
1966-01-01	9.516380000000000
1967-01-01	9.199060000000001
1968-01-01	8.940710000000001
1969-01-01	8.516940000000000
1970-01-01	7.040039999999999
1971-01-01	6.519090000000000
1972-01-01	7.621850000000000
1973-01-01	8.360630000000000
1974-01-01	9.252310000000001
1975-01-01	10.189700000000000
1976-01-01	12.475600000000000
1977-01-01	12.928700000000000
1978-01-01	11.169600000000000
1979-01-01	12.519700000000000
1980-01-01	11.943400000000000
1981-01-01	12.697500000000000
1982-01-01	14.607800000000000
1983-01-01	16.308100000000000
1984-01-01	18.280100000000000
1985-01-01	19.454000000000000
1986-01-01	19.242700000000000
1987-01-01	19.643200000000000
1988-01-01	25.133200000000000
1989-01-01	28.412000000000000
1990-01-01	26.837500000000000
1991-01-01	23.021300000000000
1992-01-01	19.938200000000000
1993-01-01	18.097400000000000
1994-01-01	16.386900000000000
1995-01-01	15.368300000000000
1996-01-01	14.321500000000000
1997-01-01	13.821200000000000
1998-01-01	12.428600000000000
1999-01-01	12.904700000000000
2000-01-01	13.110700000000000
2001-01-01	13.445000000000000
2002-01-01	14.421600000000000
2003-01-01	15.099300000000000
2004-01-01	15.606300000000000
2005-01-01	15.012700000000000
2006-01-01	13.237800000000000
2007-01-01	11.992000000000000
2008-01-01	10.944900000000000
2009-01-01	10.560000000000000
2010-01-01	11.015200000000000
2011-01-01	11.136800000000000
2012-01-01	11.311400000000000
2013-01-01	11.167200000000000
2014-01-01	10.503400000000000
2015-01-01	10.278900000000000
2016-01-01	10.176000000000000