Year	Percent
1991-01-01	91.67667000
1992-01-01	57.14658000
1993-01-01	37.01670000
1994-01-01	35.48110000
1995-01-01	34.10524000
1996-01-01	33.30249000
1997-01-01	31.31901000
1998-01-01	73.37109375
1999-01-01	79.74610138
2000-01-01	81.88780212
2001-01-01	78.73826599
2002-01-01	79.80771637
2003-01-01	78.48844147
2004-01-01	79.98400879
2005-01-01	75.55115509
2006-01-01	74.99308014
2007-01-01	76.49908447
2008-01-01	74.27514267
2009-01-01	74.43798065
2010-01-01	72.41058731
2011-01-01	74.82257843
2012-01-01	70.79223633
2013-01-01	69.48826599