Year	Percent
1990-01-01	30.380300000000000
1991-01-01	30.546100000000000
1992-01-01	30.384500000000000
1993-01-01	31.486100000000000
1994-01-01	32.095200000000000
1995-01-01	27.208500000000000
1996-01-01	21.913200000000000
1997-01-01	25.438800000000000
1998-01-01	26.926900000000000
1999-01-01	33.629300000000000
2000-01-01	30.909800000000000
2001-01-01	31.228600000000000
2002-01-01	30.028000000000002
2003-01-01	29.306300000000000
2004-01-01	31.524500000000000
2005-01-01	34.579600000000000
2006-01-01	34.226700000000000
2007-01-01	34.375600000000000
2008-01-01	36.143400000000000
2009-01-01	33.566500000000000
2010-01-01	29.793100000000000
2011-01-01	28.044200000000000
2012-01-01	23.179300000000000
2013-01-01	21.536200000000000
