Year	Number
2004-01-01	20416
2005-01-01	22900
2006-01-01	25687
2007-01-01	29333
2008-01-01	31932
2009-01-01	33801
2010-01-01	36329
2011-01-01	36803
2012-01-01	40770
2013-01-01	41468
2014-01-01	43715
2015-01-01	46627
2016-01-01	48945