Year Percent 1993-01-01 1.3384600000000000 1994-01-01 1.3484900000000000 1995-01-01 1.3145200000000001 1996-01-01 1.2864500000000000 1997-01-01 1.3615500000000000 1998-01-01 1.3937300000000000 1999-01-01 2.0220599999999997 2000-01-01 2.4000400000000000 2001-01-01 2.6793299999999998 2002-01-01 2.9027900000000000 2003-01-01 3.1574100000000000 2004-01-01 2.9853000000000000 2005-01-01 2.7670100000000000 2006-01-01 2.9323799999999998 2007-01-01 3.0026200000000003 2008-01-01 2.9277400000000000 2009-01-01 2.9410000000000003 2010-01-01 2.7564000000000000 2011-01-01 2.6879400000000000 2012-01-01 2.5516700000000000 2013-01-01 2.5254100000000000 2014-01-01 2.4629500000000000 2015-01-01 2.4856000000000000