Year Percent 1980-01-01 7.0144100000000010 1981-01-01 7.0869899999999990 1982-01-01 6.3681400000000000 1983-01-01 4.6029200000000000 1984-01-01 4.2167100000000000 1985-01-01 5.0354600000000000 1986-01-01 4.2688100000000000 1987-01-01 2.6872200000000000 1988-01-01 1.6762400000000002 1989-01-01 1.0581000000000000 1990-01-01 0.5278200000000000 1991-01-01 1.9530800000000000 1992-01-01 1.7890300000000000 1993-01-01 1.7751700000000001 1994-01-01 1.1597899999999999 1995-01-01 1.0940299999999998 1996-01-01 1.1794600000000000 1997-01-01 1.2831900000000000 1998-01-01 1.3829100000000000 1999-01-01 1.9141200000000000 2000-01-01 2.0428599999999997 2001-01-01 1.9908000000000000 2002-01-01 2.5677300000000000 2003-01-01 3.8943900000000000 2004-01-01 5.3227500000000000 2005-01-01 5.3359500000000000 2006-01-01 5.5794100000000000 2007-01-01 4.4064400000000000 2008-01-01 3.6088300000000000 2009-01-01 4.2053900000000000 2010-01-01 4.4167700000000000 2011-01-01 4.1555700000000000 2012-01-01 4.5520200000000000 2013-01-01 4.4652600000000000 2014-01-01 4.5681300000000000 2015-01-01 4.2935500000000000 2016-01-01 4.2072300000000000