Year	Number
2004-01-01	10.2472
2005-01-01	11.0617
2006-01-01	12.0003
2007-01-01	13.1203
2008-01-01	13.8033
2009-01-01	14.0675
2010-01-01	14.7229
2011-01-01	15.3078
2012-01-01	16.2532
2013-01-01	16.0206
2014-01-01	16.3566
2015-01-01	16.8735
2016-01-01	19.0542
2017-01-01	20.5200