Year	Number
2004-01-01	52
2005-01-01	51
2006-01-01	51
2007-01-01	49
2008-01-01	52
2009-01-01	55
2010-01-01	57
2011-01-01	57
2012-01-01	60
2013-01-01	62
2014-01-01	63
2015-01-01	66
2016-01-01	66