Year Percent 1993-01-01 68.36600000000000 1994-01-01 64.23360000000000 1995-01-01 62.81760000000000 1996-01-01 66.60880000000000 1997-01-01 68.30430000000000 1998-01-01 63.31840000000000 1999-01-01 61.95220000000000 2000-01-01 76.11430000000000 2001-01-01 78.97330000000000 2002-01-01 82.53760000000000 2003-01-01 86.08710000000000 2004-01-01 90.52600000000001 2005-01-01 94.14950000000000 2006-01-01 96.75160000000000 2007-01-01 97.44840000000000 2008-01-01 97.81060000000000 2009-01-01 98.12820000000000 2010-01-01 98.30650000000000 2011-01-01 98.65030000000000 2012-01-01 98.85780000000000 2013-01-01 98.98380000000000 2014-01-01 99.14490000000000 2015-01-01 99.11850000000000 2016-01-01 99.20410000000000