Year Number 2004-01-01 12907 2005-01-01 13429 2006-01-01 14364 2007-01-01 16982 2008-01-01 17714 2009-01-01 18414 2010-01-01 20179 2011-01-01 21892 2012-01-01 24079 2013-01-01 31641 2014-01-01 47117 2015-01-01 40557 2016-01-01 52925