Year	Percent
1980-01-01	24.121500000000000
1981-01-01	27.483800000000000
1982-01-01	29.633000000000003
1983-01-01	31.248200000000000
1984-01-01	31.489200000000000
1985-01-01	35.977700000000000
1986-01-01	43.352100000000000
1987-01-01	48.250300000000000
1988-01-01	47.410000000000000
1989-01-01	44.798300000000000
1990-01-01	9.406880000000001
1991-01-01	8.528880000000001
1992-01-01	9.598980000000001
1993-01-01	7.779900000000000
1994-01-01	6.735020000000000
1995-01-01	5.516500000000000
1996-01-01	5.887900000000000
1997-01-01	6.942539999999999
1998-01-01	9.689670000000000
1999-01-01	8.606410000000000
2000-01-01	8.062339999999999
2001-01-01	8.626680000000000
2002-01-01	7.952439999999999
2003-01-01	8.334380000000000
2004-01-01	8.453770000000000
2005-01-01	6.872910000000001
2006-01-01	6.553889999999999
2007-01-01	5.593170000000000
2008-01-01	9.518630000000000
2009-01-01	15.225999999999999
2010-01-01	14.193800000000000
2011-01-01	13.672400000000000
2012-01-01	13.762500000000000
2013-01-01	14.627800000000000
2014-01-01	16.292100000000000
2015-01-01	15.504600000000000
2016-01-01	15.948200000000000