Year	Percent
1990-01-01	15.978600000000000
1991-01-01	15.179400000000000
1992-01-01	13.994000000000002
1993-01-01	12.022700000000000
1994-01-01	11.641400000000000
1995-01-01	11.834000000000001
1996-01-01	10.731800000000000
1997-01-01	9.869270000000000
1998-01-01	11.523500000000000
1999-01-01	14.873000000000000
2000-01-01	16.519300000000000
2001-01-01	20.567900000000000
2002-01-01	22.320100000000000
2003-01-01	22.388800000000000
2004-01-01	20.192900000000000
2005-01-01	17.808100000000000
2006-01-01	16.749100000000000
2007-01-01	16.277900000000000
2008-01-01	16.595600000000000
2009-01-01	14.196500000000000
2010-01-01	11.564100000000000
2011-01-01	10.007700000000000