Year	Number
2004-01-01	529
2005-01-01	507
2006-01-01	485
2007-01-01	456
2008-01-01	422
2009-01-01	68
2010-01-01	69
2011-01-01	69
2012-01-01	68
2013-01-01	65
2014-01-01	61
2015-01-01	61
2016-01-01	63
2017-01-01	63