Year	Number
2004-01-01	1539
2005-01-01	2197
2006-01-01	4622
2007-01-01	7100
2008-01-01	9574
2009-01-01	11193
2010-01-01	11772
2011-01-01	13557
2012-01-01	15318
2013-01-01	13923
2014-01-01	18454
2015-01-01	21952
2016-01-01	24887
2017-01-01	27371