Year	Number
2004-01-01	14
2005-01-01	17
2006-01-01	18
2007-01-01	21
2008-01-01	21
2009-01-01	21
2010-01-01	23
2011-01-01	25
2012-01-01	26
2013-01-01	51
2014-01-01	54
2015-01-01	51
2016-01-01	131