Year	Number
2004-01-01	15.7730
2005-01-01	16.7406
2006-01-01	18.5828
2007-01-01	21.0716
2008-01-01	22.3955
2009-01-01	24.3068
2010-01-01	27.4219
2011-01-01	31.1528
2012-01-01	35.3817
2013-01-01	58.8350
2014-01-01	65.7129
2015-01-01	63.9671
2016-01-01	64.7427