Year Percent Change From Preceding Period 2004-01-01 23.6415748768312 2005-01-01 47.9839249312949 2006-01-01 42.5364551183655 2007-01-01 59.1466018547105 2008-01-01 47.4023246020546 2009-01-01 16.2005206465872 2010-01-01 24.7512400826634 2011-01-01 29.0150006283222 2012-01-01 32.9050432850217 2013-01-01 29.0110792229320 2014-01-01 41.8393389799776 2015-01-01 24.4605485980928 2016-01-01 15.4207786309092 2017-01-01 13.7213450580595