Year Percent 1995-01-01 2.237850000000000 1996-01-01 3.327980000000000 1997-01-01 8.534100000000000 1998-01-01 8.280860000000000 1999-01-01 11.267000000000001 2000-01-01 15.499900000000000 2001-01-01 17.441200000000000 2002-01-01 18.806900000000000 2003-01-01 18.910400000000000 2004-01-01 18.270800000000000 2005-01-01 13.629400000000000 2006-01-01 10.897100000000000 2007-01-01 10.743300000000000 2008-01-01 7.523969999999999 2009-01-01 11.706000000000000 2010-01-01 12.447700000000000 2011-01-01 13.794100000000000 2012-01-01 20.647900000000000 2013-01-01 26.572700000000000 2014-01-01 26.550300000000000 2015-01-01 32.731800000000000 2016-01-01 30.608300000000000