Year Number 2004-01-01 583 2005-01-01 586 2006-01-01 610 2007-01-01 682 2008-01-01 658 2009-01-01 624 2010-01-01 587 2011-01-01 549 2012-01-01 400 2013-01-01 343 2014-01-01 319 2015-01-01 276 2016-01-01 261