Year	Number
2004-01-01	7598934
2005-01-01	9974733
2006-01-01	12082707
2007-01-01	13655799
2008-01-01	14308970
2009-01-01	12862186
2010-01-01	13985849
2011-01-01	14310068
2012-01-01	14950316
2013-01-01	15369654
2014-01-01	15558663
2015-01-01	15552436
2016-01-01	15794983