Year	Number
2004-01-01	13.7908
2005-01-01	14.8091
2006-01-01	16.1496
2007-01-01	17.3366
2008-01-01	17.9884
2009-01-01	17.6518
2010-01-01	16.7841
2011-01-01	16.4395
2012-01-01	16.0788
2013-01-01	15.4114
2014-01-01	15.5025
2015-01-01	15.1278
2016-01-01	14.6992