Year	Number
2004-01-01	11
2005-01-01	12
2006-01-01	14
2007-01-01	17
2008-01-01	19
2009-01-01	19
2010-01-01	22
2011-01-01	22
2012-01-01	22
2013-01-01	23
2014-01-01	23