Year Number 2008-01-01 36.7491 2009-01-01 88.1264 2010-01-01 106.5102 2011-01-01 140.3944 2012-01-01 167.5158 2013-01-01 157.3860 2014-01-01 174.9035 2015-01-01 183.5727 2016-01-01 184.5995 2017-01-01 174.5789