Year	Number
2004-01-01	1.4390
2005-01-01	2.9659
2006-01-01	3.5148
2007-01-01	7.6855
2008-01-01	11.9891
2009-01-01	14.9167
2010-01-01	17.2318
2011-01-01	19.8290
2012-01-01	20.9212
2013-01-01	22.1248
2014-01-01	22.9616
2015-01-01	24.0128
2016-01-01	24.5020
2017-01-01	25.0867