Year	Number
2004-01-01	31.6444
2005-01-01	31.6647
2006-01-01	30.4346
2007-01-01	27.0870
2008-01-01	26.4633
2009-01-01	26.0897
2010-01-01	25.3913
2011-01-01	24.7212
2012-01-01	24.0610
2013-01-01	23.8931
2014-01-01	23.3218
2015-01-01	23.0436
2016-01-01	22.7605