Year Percent 1994-01-01 7.806369999999999 1995-01-01 8.820990000000000 1996-01-01 10.367700000000000 1997-01-01 15.499100000000000 1998-01-01 21.453700000000000 1999-01-01 25.510900000000000 2000-01-01 33.658400000000000 2001-01-01 34.531300000000000 2002-01-01 38.360500000000000 2003-01-01 41.328800000000000 2004-01-01 59.818200000000000 2005-01-01 61.546600000000000 2006-01-01 69.018300000000000 2007-01-01 74.019400000000000 2008-01-01 63.834300000000000 2009-01-01 72.367100000000000 2010-01-01 65.011500000000000 2011-01-01 53.348500000000000 2012-01-01 58.616300000000000 2013-01-01 52.551400000000000 2014-01-01 54.376900000000000 2015-01-01 60.546000000000010