Year	Number
2004-01-01	35
2005-01-01	35
2006-01-01	37
2007-01-01	41
2008-01-01	41
2009-01-01	39
2010-01-01	59
2011-01-01	62
2012-01-01	64
2013-01-01	64
2014-01-01	63
2015-01-01	63
2016-01-01	54
2017-01-01	63