Year	Number
2004-01-01	17.7756
2005-01-01	17.3365
2006-01-01	16.8439
2007-01-01	16.3740
2008-01-01	15.7367
2009-01-01	15.1526
2010-01-01	14.5388
2011-01-01	13.8879
2012-01-01	13.3620
2013-01-01	12.7340
2014-01-01	12.2847
2015-01-01	11.8457
2016-01-01	11.2984
2017-01-01	6.7921