Year	Number
2004-01-01	31
2005-01-01	35
2006-01-01	43
2007-01-01	44
2008-01-01	52
2009-01-01	76
2010-01-01	90
2011-01-01	100
2012-01-01	115
2013-01-01	137
2014-01-01	143
2015-01-01	143
2016-01-01	143