Year	Number
2004-01-01	19
2005-01-01	19
2006-01-01	19
2007-01-01	19
2008-01-01	23
2009-01-01	23
2010-01-01	23
2011-01-01	23
2012-01-01	63
2013-01-01	63
2014-01-01	63
2015-01-01	73
2016-01-01	91