Year	Number
2004-01-01	21
2005-01-01	22
2006-01-01	28
2007-01-01	45
2008-01-01	49
2009-01-01	51
2010-01-01	51
2011-01-01	56
2012-01-01	58
2013-01-01	112
2014-01-01	115
2015-01-01	115