Year	Number
2004-01-01	8.8865
2005-01-01	10.1159
2006-01-01	11.2399
2007-01-01	12.9610
2008-01-01	14.1553
2009-01-01	14.5065
2010-01-01	15.1036
2011-01-01	16.2627
2012-01-01	17.3516
2013-01-01	17.7731
2014-01-01	18.6161
2015-01-01	19.2132
2016-01-01	19.0025