Year Number 2008-01-01 238.9682 2009-01-01 237.1713 2010-01-01 230.4515 2011-01-01 223.3608 2012-01-01 225.2634 2013-01-01 217.0216 2014-01-01 208.0515 2015-01-01 210.2621 2016-01-01 203.3294 2017-01-01 203.6333