Year	Number
2004-01-01	559
2005-01-01	543
2006-01-01	535
2007-01-01	523
2008-01-01	511
2009-01-01	504
2010-01-01	501
2011-01-01	498
2012-01-01	492
2013-01-01	491
2014-01-01	484
2015-01-01	481
2016-01-01	472
2017-01-01	451