Year	Number
2004-01-01	179
2005-01-01	172
2006-01-01	34
2007-01-01	31
2008-01-01	32
2009-01-01	26
2010-01-01	24
2011-01-01	24
2012-01-01	26
2013-01-01	26
2014-01-01	21
2015-01-01	20
2016-01-01	16
2017-01-01	16