Year	Number
2004-01-01	24
2005-01-01	25
2006-01-01	32
2007-01-01	35
2008-01-01	33
2009-01-01	33
2010-01-01	33
2011-01-01	34
2012-01-01	37
2013-01-01	43
2014-01-01	52
2015-01-01	60
2016-01-01	60
2017-01-01	57