Year	Percent
1960-01-01	16.011100000000000
1961-01-01	15.042600000000000
1962-01-01	15.358700000000000
1963-01-01	16.183900000000000
1964-01-01	15.924900000000000
1965-01-01	17.182700000000000
1966-01-01	16.838700000000000
1967-01-01	15.973500000000000
1968-01-01	14.911200000000000
1969-01-01	14.127200000000000
1970-01-01	15.230800000000000
1971-01-01	16.615300000000000
1972-01-01	17.574700000000000
1973-01-01	18.018500000000000
1974-01-01	18.858800000000000
1975-01-01	19.290700000000000
1976-01-01	16.526900000000000
1977-01-01	15.089400000000000
1978-01-01	14.401200000000000
1979-01-01	12.040999999999999
1980-01-01	14.782600000000000
1981-01-01	15.697200000000000
1982-01-01	16.359600000000000
1983-01-01	18.621000000000000
1984-01-01	18.274700000000000
1985-01-01	17.838800000000000
1986-01-01	15.403100000000000
1987-01-01	12.340600000000000
1988-01-01	10.048100000000000
1989-01-01	7.518530000000000
1990-01-01	7.008340000000000
1991-01-01	8.023539999999999
1992-01-01	11.302300000000000
1993-01-01	13.595700000000000
1994-01-01	15.004800000000000
1995-01-01	16.447300000000000
1996-01-01	19.916400000000000
1997-01-01	22.653100000000000
1998-01-01	25.716900000000000
1999-01-01	27.694300000000000
2000-01-01	27.262100000000000
2001-01-01	26.519200000000000
2002-01-01	25.238100000000000
2003-01-01	23.722100000000000
2004-01-01	21.649800000000000
2005-01-01	22.050400000000000
2006-01-01	22.164400000000000
2007-01-01	23.730900000000000
2008-01-01	26.987300000000000
2009-01-01	29.739200000000000
2010-01-01	28.838100000000000
2011-01-01	29.539300000000000
2012-01-01	30.773800000000000
2013-01-01	33.579800000000000
2014-01-01	35.137200000000000
2015-01-01	36.620400000000000
2016-01-01	36.781600000000000