Year	Number
2004-01-01	21704084
2005-01-01	21468704
2006-01-01	23596774
2007-01-01	26669232
2008-01-01	26152372
2009-01-01	28168556
2010-01-01	27916976
2011-01-01	28588666
2012-01-01	29097912
2013-01-01	32985370
2014-01-01	34403928
2015-01-01	33634399
2016-01-01	33172014
2017-01-01	38901870