Year	Percent
1960-01-01	11.382500000000000
1961-01-01	12.356500000000000
1962-01-01	13.082100000000000
1963-01-01	11.860100000000000
1964-01-01	12.676800000000000
1965-01-01	13.596500000000000
1966-01-01	14.392400000000000
1967-01-01	16.644300000000000
1968-01-01	17.002800000000000
1969-01-01	12.639000000000001
1970-01-01	9.323950000000000
1971-01-01	10.191400000000000
1972-01-01	10.470100000000000
1973-01-01	10.641100000000000
1974-01-01	10.016100000000000
1975-01-01	15.129700000000000
1976-01-01	17.300200000000000
1977-01-01	20.227000000000000
1978-01-01	21.271700000000000
1979-01-01	20.651900000000000
1980-01-01	23.962600000000000
1981-01-01	29.836100000000000
1982-01-01	29.735000000000000
1983-01-01	31.248700000000000
1984-01-01	33.864000000000004
1985-01-01	30.952100000000000
1986-01-01	31.524000000000000
1987-01-01	23.270700000000000
1988-01-01	24.432700000000000
1989-01-01	20.719000000000000
1990-01-01	10.172600000000000
1991-01-01	11.457300000000000
1992-01-01	12.006700000000000
1993-01-01	13.935500000000000
1994-01-01	13.433500000000000
1995-01-01	10.919000000000000
1996-01-01	9.608920000000000
1997-01-01	9.918520000000000
1998-01-01	10.491900000000000
1999-01-01	11.759500000000000
2000-01-01	12.657300000000000
2001-01-01	14.997900000000000
2002-01-01	13.021600000000000
2003-01-01	12.472999999999999
2004-01-01	11.048100000000000
2005-01-01	11.120700000000000
2006-01-01	11.046300000000000
2007-01-01	14.306600000000000
2008-01-01	18.974500000000000
2009-01-01	22.221200000000000
2010-01-01	20.514700000000000
2011-01-01	19.581000000000000
2012-01-01	20.261900000000000
2013-01-01	20.587600000000000
2014-01-01	19.825400000000000
2015-01-01	19.520400000000000
2016-01-01	19.494700000000000