Year	Number
2005-01-01	38
2006-01-01	41
2007-01-01	40
2008-01-01	39
2009-01-01	38
2010-01-01	37
2011-01-01	36
2012-01-01	36
2013-01-01	39
2014-01-01	36
2015-01-01	39
2016-01-01	40
2017-01-01	31