Year Number 2004-01-01 131.8611 2005-01-01 166.2639 2006-01-01 196.5453 2007-01-01 233.1167 2008-01-01 258.4674 2009-01-01 257.0312 2010-01-01 251.3498 2011-01-01 252.2286 2012-01-01 258.5709 2013-01-01 258.1929 2014-01-01 257.9513 2015-01-01 258.7334 2016-01-01 254.6573 2017-01-01 254.9666