Year	Number
2004-01-01	51.8665
2005-01-01	52.0342
2006-01-01	51.1553
2007-01-01	53.1443
2008-01-01	55.1607
2009-01-01	54.7716
2010-01-01	54.1544
2011-01-01	35.0774
2012-01-01	35.5932
2013-01-01	35.0037
2014-01-01	34.5247
2015-01-01	34.1931
2016-01-01	27.2937
2017-01-01	28.4359