Year	Number
2004-01-01	252
2005-01-01	252
2006-01-01	256
2007-01-01	260
2008-01-01	273
2009-01-01	278
2010-01-01	280
2011-01-01	284
2012-01-01	273
2013-01-01	277
2014-01-01	276
2015-01-01	271
2016-01-01	263
2017-01-01	263