Year	Number
2004-01-01	9
2005-01-01	10
2006-01-01	17
2007-01-01	21
2008-01-01	23
2009-01-01	27
2010-01-01	32
2011-01-01	32
2012-01-01	32
2013-01-01	33
2014-01-01	32
2015-01-01	32
2016-01-01	34