Year Percent 1982-01-01 9.803250000000000 1983-01-01 10.104700000000000 1984-01-01 12.517400000000000 1985-01-01 11.574500000000000 1986-01-01 9.469520000000000 1987-01-01 10.601300000000000 1988-01-01 12.724100000000000 1989-01-01 13.574800000000000 1990-01-01 14.114400000000000 1991-01-01 15.403700000000000 1992-01-01 15.884700000000000 1993-01-01 14.447100000000000 1994-01-01 13.657200000000000 1995-01-01 13.203200000000000 1996-01-01 11.015200000000000 1997-01-01 11.968000000000000 1998-01-01 12.311300000000000 1999-01-01 11.606100000000000 2000-01-01 11.389200000000000 2001-01-01 9.750000000000000 2002-01-01 8.332760000000000 2003-01-01 8.537910000000000 2004-01-01 8.490969999999999 2005-01-01 8.347650000000000 2006-01-01 8.826580000000000 2007-01-01 9.052060000000000 2008-01-01 9.852789999999999 2009-01-01 12.897800000000000 2010-01-01 16.829200000000000 2011-01-01 17.314500000000000 2012-01-01 18.708100000000000 2013-01-01 19.725600000000000 2014-01-01 23.413200000000000 2015-01-01 24.786800000000000 2016-01-01 26.308800000000000