Year	Number
2004-01-01	11
2005-01-01	12
2006-01-01	12
2007-01-01	10
2008-01-01	12
2009-01-01	20
2010-01-01	17
2011-01-01	26
2012-01-01	26
2013-01-01	28
2014-01-01	27
2015-01-01	24
2016-01-01	23
2017-01-01	21