Year	Number
2007-01-01	446
2008-01-01	481
2009-01-01	492
2010-01-01	506
2011-01-01	520
2012-01-01	521
2013-01-01	570
2014-01-01	596
2015-01-01	600
2016-01-01	607
2017-01-01	588
