Year Percent 1992-01-01 6.0611300000000000 1993-01-01 5.9525300000000000 1994-01-01 6.0098199999999995 1995-01-01 6.1551599999999995 1996-01-01 6.3230900000000005 1997-01-01 7.6716700000000000 1998-01-01 8.8157000000000000 1999-01-01 10.9509999999999990 2000-01-01 13.3220000000000010 2001-01-01 18.2222000000000000 2002-01-01 27.5577000000000000 2003-01-01 35.4872000000000000 2004-01-01 34.3347000000000000 2005-01-01 31.7969999999999970 2006-01-01 41.6902000000000000 2007-01-01 39.9731000000000000 2008-01-01 26.7493000000000000 2009-01-01 28.3650000000000000 2010-01-01 22.1164000000000000 2011-01-01 20.1452000000000000 2012-01-01 19.0933000000000000 2013-01-01 19.5150000000000000 2014-01-01 21.7933000000000000 2015-01-01 27.7031000000000000 2016-01-01 30.2064000000000000