Year Percent 1993-01-01 0.1853270000000000 1994-01-01 0.4812120000000000 1995-01-01 0.6036900000000000 1996-01-01 1.0302400000000000 1997-01-01 1.5458500000000000 1998-01-01 2.0039100000000000 1999-01-01 3.0239400000000000 2000-01-01 2.9532000000000000 2001-01-01 2.9891000000000000 2002-01-01 3.0093799999999997 2003-01-01 3.3542900000000000 2004-01-01 3.7945300000000004 2005-01-01 3.6501200000000000 2006-01-01 3.2226700000000000 2007-01-01 2.6288000000000000 2008-01-01 2.2446900000000003 2009-01-01 2.0811500000000000 2010-01-01 1.7109400000000001 2011-01-01 1.5331900000000000 2012-01-01 2.3170400000000000 2013-01-01 2.7758599999999998 2014-01-01 2.3125500000000000 2015-01-01 1.9128000000000000 2016-01-01 1.6254100000000000