Year Percent 1997-01-01 142.14100000000000 1998-01-01 139.52200000000002 1999-01-01 139.52200000000002 2000-01-01 139.52200000000002 2001-01-01 79.27820000000000 2002-01-01 148.35399999999998 2003-01-01 136.80800000000000 2004-01-01 132.10299999999998 2005-01-01 134.44000000000000 2006-01-01 124.82500000000000 2007-01-01 114.14900000000000 2008-01-01 112.71600000000001 2009-01-01 118.72600000000000 2010-01-01 113.11700000000000 2011-01-01 105.60300000000000 2012-01-01 101.67399999999999 2013-01-01 102.93700000000001 2014-01-01 110.07300000000000 2015-01-01 105.69800000000000 2016-01-01 99.32000000000000