Year Percent 1994-01-01 33.391998290 1995-01-01 5.992000103 1996-01-01 17.872999190 1997-01-01 16.691999440 1998-01-01 18.041999820 1999-01-01 19.774999620 2000-01-01 20.742000580 2001-01-01 18.533000950 2002-01-01 16.191999440 2003-01-01 14.411000250 2004-01-01 14.074000360 2005-01-01 13.185999870 2006-01-01 9.213000298 2007-01-01 6.647999763 2008-01-01 5.474999905 2009-01-01 5.288000107 2010-01-01 6.758999825 2011-01-01 5.829999924 2012-01-01 5.823999882 2013-01-01 5.972000122