Year	Percent
1976-01-01	34.860400000000000
1977-01-01	29.202300000000000
1978-01-01	30.338900000000000
1979-01-01	29.059800000000000
1980-01-01	26.603900000000000
1981-01-01	26.603900000000000
1982-01-01	37.274800000000000
1983-01-01	38.651300000000000
1984-01-01	38.152300000000000
1985-01-01	38.205999999999996
1986-01-01	36.111900000000000
1987-01-01	35.270400000000000
1988-01-01	35.941500000000000
1989-01-01	35.916200000000000
1990-01-01	36.853200000000000
1991-01-01	39.951300000000000
1992-01-01	39.461000000000000
1993-01-01	38.865000000000000
1994-01-01	38.613400000000000
1995-01-01	38.638200000000000
1996-01-01	39.931700000000000
1997-01-01	43.142800000000000
1998-01-01	46.996700000000000
1999-01-01	48.015900000000000
2000-01-01	45.229400000000000
2001-01-01	47.344700000000000
2002-01-01	49.370800000000000
2003-01-01	51.256800000000000
2004-01-01	54.467700000000000
2005-01-01	56.810000000000000
2006-01-01	55.895600000000000
2007-01-01	59.016400000000000
2008-01-01	64.699800000000000
2009-01-01	69.601900000000000
2010-01-01	70.085100000000000
2011-01-01	66.303500000000000
2012-01-01	61.799100000000000
2013-01-01	61.495900000000000
2014-01-01	60.157300000000000
2015-01-01	60.845000000000000
2016-01-01	63.279800000000000