Year Percent 1995-01-01 34.9722357725000 1996-01-01 34.7086487825000 1997-01-01 34.2311271400000 1998-01-01 33.4287349775000 1999-01-01 32.0228846900000 2000-01-01 31.5051827750000 2001-01-01 31.6708591675000 2002-01-01 30.7434094025000 2003-01-01 30.0851559700000 2004-01-01 29.6455090125000 2005-01-01 29.2859728975000 2006-01-01 29.0255803125000 2007-01-01 27.9867316075000 2008-01-01 27.6329585350000 2009-01-01 26.7664845950000 2010-01-01 26.3770367650000 2011-01-01 26.0101709925000 2012-01-01 23.1166666666667 2013-01-01 22.9916666666667 2014-01-01 21.6250000000000 2015-01-01 21.9500000000000 2016-01-01 21.4583333333333 2017-01-01 21.2250000000000