Year	Number
2004-01-01	0.0682
2005-01-01	0.1203
2006-01-01	0.2607
2007-01-01	0.3914
2008-01-01	0.5751
2009-01-01	0.7981
2010-01-01	1.0339
2011-01-01	1.3066
2012-01-01	1.6155
2013-01-01	1.8721
2014-01-01	2.0767
2015-01-01	2.2267