Year	Number
2004-01-01	10
2005-01-01	12
2006-01-01	13
2007-01-01	14
2008-01-01	14
2009-01-01	16
2010-01-01	19
2011-01-01	20
2012-01-01	25
2013-01-01	27
2014-01-01	31
2015-01-01	32