Year	Number
2004-01-01	20349
2005-01-01	24978
2006-01-01	23528
2007-01-01	19750
2008-01-01	26661
2009-01-01	30800
2010-01-01	36771
2011-01-01	43409
2012-01-01	48897
2013-01-01	39898
2014-01-01	42579
2015-01-01	51589