Year Number 2004-01-01 540 2005-01-01 610 2006-01-01 635 2007-01-01 703 2008-01-01 754 2009-01-01 619 2010-01-01 624 2011-01-01 656 2012-01-01 519 2013-01-01 448 2014-01-01 367 2015-01-01 316