Year	Number
2004-01-01	160
2005-01-01	168
2006-01-01	172
2007-01-01	215
2008-01-01	233
2009-01-01	239
2010-01-01	211
2011-01-01	254
2012-01-01	278
2013-01-01	287
2014-01-01	293
2015-01-01	314
2016-01-01	324
2017-01-01	319