Year	Number
2004-01-01	14.0684
2005-01-01	14.1006
2006-01-01	15.3065
2007-01-01	18.4417
2008-01-01	20.4836
2009-01-01	21.2287
2010-01-01	21.8670
2011-01-01	19.4051
2012-01-01	20.4246
2013-01-01	18.9259
2014-01-01	17.1599
2015-01-01	17.0151
2016-01-01	16.5809
