Year Number 2007-01-01 29944 2008-01-01 39249 2009-01-01 40017 2010-01-01 31878 2011-01-01 25267 2012-01-01 22551 2013-01-01 22644 2014-01-01 23003 2015-01-01 26611 2016-01-01 28702 2017-01-01 30714