Year Number 2004-01-01 1063 2005-01-01 1601 2006-01-01 2231 2007-01-01 4053 2008-01-01 4734 2009-01-01 9139 2010-01-01 9108 2011-01-01 10297 2012-01-01 18389 2013-01-01 7043 2014-01-01 9166 2015-01-01 15064 2016-01-01 18906