Year Number 2006-01-01 30377.25 2007-01-01 37998.75 2008-01-01 41277.50 2009-01-01 42972.00 2010-01-01 43156.50 2011-01-01 42846.50 2012-01-01 43231.50 2013-01-01 45665.50 2014-01-01 49533.25 2015-01-01 52896.25 2016-01-01 57438.00 2017-01-01 60944.75