Year	Number
2004-01-01	30.8133
2005-01-01	30.5819
2006-01-01	29.9228
2007-01-01	29.9144
2008-01-01	29.7595
2009-01-01	29.6473
2010-01-01	29.1992
2011-01-01	28.5932
2012-01-01	27.0846
2013-01-01	25.9265
2014-01-01	25.2592
2015-01-01	24.5522
2016-01-01	24.0905
2017-01-01	24.2647
