Year Percent 1980-01-01 9.71045 1981-01-01 12.43180 1982-01-01 12.91910 1983-01-01 12.45330 1984-01-01 13.15310 1985-01-01 16.56450 1986-01-01 16.41510 1987-01-01 18.31640 1988-01-01 18.44570 1989-01-01 19.88510 1990-01-01 19.42290 1991-01-01 20.42410 1992-01-01 18.90630 1993-01-01 21.13160 1994-01-01 23.68920 1995-01-01 23.96070 1996-01-01 24.24060 1997-01-01 26.48790 1998-01-01 31.37930 1999-01-01 32.06630 2000-01-01 38.53910 2001-01-01 43.42760 2002-01-01 53.66210 2003-01-01 60.59490 2004-01-01 63.33740 2005-01-01 64.30180 2006-01-01 77.54790 2007-01-01 84.67760 2008-01-01 80.69400 2009-01-01 90.07250 2010-01-01 86.11050 2011-01-01 75.57040 2012-01-01 77.08570 2013-01-01 75.42110 2014-01-01 62.42190 2015-01-01 63.55280 2016-01-01 58.74380