Year Percent 1991-01-01 4.6695600000000000 1992-01-01 3.8640300000000000 1993-01-01 4.0975199999999990 1994-01-01 4.5175199999999990 1995-01-01 5.5515300000000005 1996-01-01 7.2129400000000000 1997-01-01 8.5311300000000010 1998-01-01 10.0275000000000000 1999-01-01 10.0275000000000000 2000-01-01 11.9227000000000000 2001-01-01 15.5511000000000000 2002-01-01 14.7212000000000000 2003-01-01 12.3546000000000000 2004-01-01 10.9046000000000000 2005-01-01 11.9063000000000000 2006-01-01 16.5030000000000000 2007-01-01 14.1669000000000000 2008-01-01 10.2888000000000000 2009-01-01 15.7114000000000000 2010-01-01 21.1536000000000000 2011-01-01 22.7196000000000000 2012-01-01 16.2485000000000000 2013-01-01 11.0526000000000000 2014-01-01 10.3539000000000000 2015-01-01 10.9492000000000000 2016-01-01 10.7748000000000000