Year	Number
2004-01-01	50
2005-01-01	53
2006-01-01	53
2007-01-01	53
2008-01-01	55
2009-01-01	55
2010-01-01	55
2011-01-01	59
2012-01-01	61
2013-01-01	61
2014-01-01	61
2015-01-01	63
2016-01-01	66