Year	Number
2004-01-01	35.3430
2005-01-01	38.5447
2006-01-01	41.4761
2007-01-01	45.0312
2008-01-01	46.7775
2009-01-01	47.3903
2010-01-01	48.6370
2011-01-01	50.0125
2012-01-01	52.1544
2013-01-01	53.6724
2014-01-01	56.2950
2015-01-01	56.8773
2016-01-01	57.5011
2017-01-01	58.1042