Year	Number
2004-01-01	2.4939
2005-01-01	4.0745
2006-01-01	6.3224
2007-01-01	11.8721
2008-01-01	18.8971
2009-01-01	24.6575
2010-01-01	27.7134
2011-01-01	35.4408
2012-01-01	41.0959
2013-01-01	44.0815
2014-01-01	48.7179
2015-01-01	49.7366
2016-01-01	50.2986