Year Percent 1996-01-01 3.3343300000000005 1997-01-01 3.3984300000000003 1998-01-01 3.4300800000000002 1999-01-01 3.1658000000000000 2000-01-01 3.3478800000000004 2001-01-01 3.5936900000000000 2002-01-01 3.6891000000000000 2003-01-01 3.5158600000000000 2004-01-01 3.5382100000000000 2005-01-01 3.5551600000000000 2006-01-01 3.6876400000000000 2007-01-01 3.5319800000000003 2008-01-01 3.2560500000000000 2009-01-01 3.0673200000000000 2010-01-01 2.9232099999999996 2011-01-01 2.8680900000000000 2012-01-01 2.7611500000000000 2013-01-01 2.7247000000000000 2014-01-01 2.6781599999999997 2015-01-01 2.5869800000000000 2016-01-01 2.7786400000000000