Year	Number
2004-01-01	14.4910
2005-01-01	16.8054
2006-01-01	18.0534
2007-01-01	19.1799
2008-01-01	20.4282
2009-01-01	24.1816
2010-01-01	32.6168
2011-01-01	35.0118
2012-01-01	41.2883
2013-01-01	33.9199
2014-01-01	36.8163
2015-01-01	39.3627