Year	Number
2004-01-01	3.8696
2005-01-01	7.0199
2006-01-01	6.1842
2007-01-01	6.9975
2008-01-01	8.1313
2009-01-01	9.2852
2010-01-01	10.1837
2011-01-01	11.2570
2012-01-01	12.2698
2013-01-01	13.2041
2014-01-01	13.9682
2015-01-01	14.6292
2016-01-01	15.2834
2017-01-01	15.6868