Year	Number
2004-01-01	4.5933
2005-01-01	5.0168
2006-01-01	5.5299
2007-01-01	6.1931
2008-01-01	7.0715
2009-01-01	9.9574
2010-01-01	10.7685
2011-01-01	11.4990
2012-01-01	12.2474
2013-01-01	12.8389
2014-01-01	13.2960
2015-01-01	13.7979
2016-01-01	14.1205
2017-01-01	14.2729