Year Number 2004-01-01 138 2005-01-01 139 2006-01-01 148 2007-01-01 144 2008-01-01 197 2009-01-01 266 2010-01-01 276 2011-01-01 238 2012-01-01 252 2013-01-01 253 2014-01-01 313