Year	Number
2004-01-01	38
2005-01-01	39
2006-01-01	39
2007-01-01	40
2008-01-01	41
2009-01-01	41
2010-01-01	41
2011-01-01	40
2012-01-01	39
2013-01-01	39
2014-01-01	38
2015-01-01	36
2016-01-01	36