Year Percent 1994-01-01 3.0967599999999997 1995-01-01 2.9211000000000000 1996-01-01 2.9041600000000000 1997-01-01 3.7816400000000003 1998-01-01 3.6799000000000000 1999-01-01 3.6769600000000000 2000-01-01 4.1181600000000000 2001-01-01 5.0625400000000000 2002-01-01 6.0311500000000000 2003-01-01 6.6700800000000005 2004-01-01 8.2236900000000000 2005-01-01 11.9643000000000000 2006-01-01 18.0396000000000000 2007-01-01 24.8005000000000000 2008-01-01 30.9991000000000000 2009-01-01 34.8424000000000000 2010-01-01 35.4154000000000000 2011-01-01 37.5591000000000000 2012-01-01 38.7430000000000000 2013-01-01 38.1747000000000000 2014-01-01 37.1719000000000000 2015-01-01 36.2413000000000000 2016-01-01 34.5443000000000000