Year	Number
2004-01-01	13.0998
2005-01-01	14.0832
2006-01-01	15.3443
2007-01-01	16.4714
2008-01-01	17.0963
2009-01-01	16.6133
2010-01-01	15.7848
2011-01-01	15.4424
2012-01-01	15.0447
2013-01-01	14.3930
2014-01-01	14.4482
2015-01-01	14.0727
2016-01-01	13.6529