Year Percent Change from Year Ago 1998-01-01 8.669103055388260 1999-01-01 10.524366595070300 2000-01-01 9.456198340791840 2001-01-01 5.319139424076580 2002-01-01 5.928027495306330 2003-01-01 2.954744624609950 2004-01-01 6.571101290133190 2005-01-01 5.667736698415720 2006-01-01 5.044522621969620 2007-01-01 5.309118310824680 2008-01-01 -4.405380555419300 2009-01-01 -5.022238990710030 2010-01-01 1.922042204995760 2011-01-01 3.720998588864700 2012-01-01 0.182645432381044 2013-01-01 1.336921166458730 2014-01-01 8.800530320666760 2015-01-01 25.117251843162500 2016-01-01 4.987582014555470 2017-01-01 7.221787739638360