Year	Number
2004-01-01	13
2005-01-01	18
2006-01-01	21
2007-01-01	23
2008-01-01	24
2009-01-01	26
2010-01-01	30
2011-01-01	37
2012-01-01	44
2013-01-01	46
2014-01-01	51
2015-01-01	57
