Year	Number
2004-01-01	42
2005-01-01	43
2006-01-01	48
2007-01-01	55
2008-01-01	62
2009-01-01	66
2010-01-01	66
2011-01-01	65
2012-01-01	63
2013-01-01	59
2014-01-01	60
2015-01-01	58
2016-01-01	55
2017-01-01	55