Year	Number
2004-01-01	10.4591
2005-01-01	12.1499
2006-01-01	17.5055
2007-01-01	21.0191
2008-01-01	28.4854
2009-01-01	32.7563
2010-01-01	39.1822
2011-01-01	44.5788
2012-01-01	52.7245
2013-01-01	56.3027
2014-01-01	60.1701
2015-01-01	57.9312
2016-01-01	55.5901
2017-01-01	51.5867