Year	Percent
1965-01-01	11.277999999999999
1966-01-01	10.704300000000000
1967-01-01	11.687500000000000
1968-01-01	12.781300000000000
1969-01-01	13.687400000000000
1970-01-01	7.837230000000000
1971-01-01	7.537389999999999
1972-01-01	8.321960000000000
1973-01-01	9.583280000000000
1974-01-01	10.329500000000000
1975-01-01	9.978819999999999
1976-01-01	9.303410000000001
1977-01-01	9.563300000000000
1978-01-01	10.530800000000000
1979-01-01	11.169800000000000
1980-01-01	9.786380000000000
1981-01-01	10.844600000000000
1982-01-01	11.536200000000000
1983-01-01	10.965500000000000
1984-01-01	11.642700000000000
1985-01-01	10.950000000000000
1986-01-01	10.905500000000000
1987-01-01	12.988000000000000
1988-01-01	11.730800000000000
1989-01-01	9.924740000000000
1990-01-01	10.029200000000000
1991-01-01	8.915239999999999
1992-01-01	10.456800000000000
1993-01-01	9.319430000000000
1994-01-01	10.606300000000000
1995-01-01	7.964239999999999
1996-01-01	7.349100000000000
1997-01-01	6.876850000000000
1998-01-01	6.881100000000000
1999-01-01	7.869700000000000
2000-01-01	8.634480000000000
2001-01-01	9.718660000000000
2002-01-01	9.643260000000000
2003-01-01	9.942140000000000
2004-01-01	10.427100000000000
2005-01-01	11.481400000000000
2006-01-01	10.941100000000000
2007-01-01	12.062600000000000
2008-01-01	13.372600000000000
2009-01-01	14.747800000000000
2010-01-01	16.460600000000000
2011-01-01	18.633000000000000
2012-01-01	19.816800000000000
2013-01-01	18.980600000000000
2014-01-01	18.826200000000000
2015-01-01	18.105200000000000
2016-01-01	17.712100000000000