Year	Number
2004-01-01	0.8107
2005-01-01	1.6214
2006-01-01	1.5809
2007-01-01	2.3916
2008-01-01	10.4986
2009-01-01	11.5525
2010-01-01	11.8768
2011-01-01	13.5792
2012-01-01	14.3899
2013-01-01	15.6871
2014-01-01	15.8087
2015-01-01	17.0247
2016-01-01	17.7138
2017-01-01	17.9570