Year	Number
2004-01-01	19.0477
2005-01-01	19.4421
2006-01-01	21.1728
2007-01-01	22.6185
2008-01-01	25.9941
2009-01-01	27.2554
2010-01-01	33.0829
2011-01-01	36.3674
2012-01-01	36.5481
2013-01-01	41.3729
2014-01-01	44.5468
2015-01-01	45.9332
2016-01-01	50.7965
2017-01-01	50.6407