Year	Number
2004-01-01	440716.0
2005-01-01	323577.0
2006-01-01	295596.5
2007-01-01	281644.0
2008-01-01	271911.0
2009-01-01	243769.0
2010-01-01	260767.0
2011-01-01	305360.0
2012-01-01	384350.0
2013-01-01	466054.0
2014-01-01	603819.0
2015-01-01	523448.0
2016-01-01	538290.0
2017-01-01	465958.0