Year Percent 1994-01-01 0.28803800000000000 1995-01-01 0.37598100000000000 1996-01-01 0.38126100000000000 1997-01-01 0.24860200000000000 1998-01-01 0.15209800000000000 1999-01-01 0.06953700000000000 2000-01-01 0.12198599999999998 2001-01-01 0.05247000000000000 2002-01-01 0.03138000000000000 2003-01-01 0.08818400000000000 2004-01-01 0.18652300000000000 2005-01-01 0.29063900000000000 2006-01-01 0.46140299999999995 2007-01-01 0.56849300000000000 2008-01-01 0.37512900000000000 2009-01-01 0.73595600000000000 2010-01-01 0.63777299999999990 2011-01-01 0.13301200000000000 2012-01-01 0.14028600000000000