Year	Number
2004-01-01	23.7642
2005-01-01	25.4951
2006-01-01	27.9504
2007-01-01	29.9335
2008-01-01	29.7221
2009-01-01	29.5153
2010-01-01	29.0535
2011-01-01	18.9955
2012-01-01	19.2729
2013-01-01	18.0764
2014-01-01	16.2398
2015-01-01	14.5512
2016-01-01	13.4268
2017-01-01	13.3860