Year Number 2004-01-01 344 2005-01-01 334 2006-01-01 334 2007-01-01 341 2008-01-01 350 2009-01-01 375 2010-01-01 381 2011-01-01 390 2012-01-01 250 2013-01-01 281 2015-01-01 291