Year	Number
2004-01-01	151
2005-01-01	158
2006-01-01	173
2007-01-01	202
2008-01-01	200
2009-01-01	234
2010-01-01	276
2011-01-01	333
2012-01-01	389
2013-01-01	419
2014-01-01	483
2015-01-01	536
2016-01-01	557