Year Percent 1990-01-01 16.2609000000000000 1991-01-01 30.0843000000000000 1992-01-01 28.4317000000000000 1993-01-01 31.9947000000000000 1994-01-01 33.5018000000000000 1995-01-01 35.3756000000000000 1996-01-01 43.5010000000000050 1997-01-01 37.6104000000000000 1998-01-01 31.6289000000000000 1999-01-01 28.5374000000000000 2000-01-01 27.7959000000000000 2001-01-01 26.9603000000000000 2002-01-01 56.6032000000000000 2003-01-01 15.7146000000000000 2004-01-01 13.7126000000000000 2005-01-01 8.6826500000000000 2006-01-01 7.0129199999999990 2007-01-01 7.6412900000000000 2008-01-01 14.8184000000000000 2009-01-01 10.7223000000000000 2010-01-01 5.5281199999999995 2011-01-01 5.1821300000000000 2012-01-01 7.3192699999999995 2013-01-01 11.8348000000000000 2014-01-01 10.1419000000000000 2015-01-01 9.4718700000000000 2016-01-01 9.6173200000000000