Year	Number
2004-01-01	10.8384
2005-01-01	12.3001
2006-01-01	13.6794
2007-01-01	15.8084
2008-01-01	17.3137
2009-01-01	17.7905
2010-01-01	18.5556
2011-01-01	19.9835
2012-01-01	21.2833
2013-01-01	21.7406
2014-01-01	22.7115
2015-01-01	23.3951
2016-01-01	23.0981